Product
Folder
Sample &
Buy
Support &
Community
Tools &
Software
Technical
Documents
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
TSC2013-Q1 12-Bit, Nanopower, 4-Wire
Dual-Touch Screen Controller With I2C Interface
1 Features
2 Applications
•
•
•
•
•
•
•
1
•
•
•
•
•
•
•
•
•
•
Qualified for Automotive Applications
AEC-Q100 Qualified With the Following Results:
– Device Temperature Grade 1: –40°C to 125°C
– Device HBM ESD Classification Level 2
– Device CDM ESD Classification Level C4B
4-Wire Touch Screen Interface
Ratiometric Conversion
Single 1.6-V to 3.6-V Supply:
– I/OVDD 1.2 to 3.6 V
– SNSVDD: 1.6 to 3.6 V
Preprocessing to Reduce Bus Activity
High-Speed I2C-Compatible Interface
Internal Detection of Screen Touch
Register-Based Programmable:
– 10-Bit or 12-Bit Resolution
– Sampling Rates
– System Timing
Touch Pressure Measurement
Auto Power-Down Control
Low Power:
– 430 μA at 1.8 V, 50 SSPS
– 320 μA at 1.6 V, 50 SSPS
– 58 μA at 1.6 V, 8.2 kSPS Eq. Rate
Automotive Infotainment Display
Automotive Navigation System
Industrial User Interfaces
Medical Devices
Portable Consumer Electronics
3 Description
The TSC2013-Q1 device is a very low-power dualtouch screen controller designed to work with powersensitive, low-cost touch-screen displays in
automotive infotainment and navigation systems. It
contains a complete, ultralow-power, 12-bit, analogto-digital (ADC) resistive touch-screen converter,
including drivers and the control logic to measure
touch pressure.
The TSC2013-Q1 device enables pinch, rotate, and
zoom functionality over a standard four-wire interface.
The device supports an I2C serial bus and data
transmission protocol in all three defined modes:
standard, fast, and high-speed. The 10 or 12-bit ADC
within is easily programmable to customize system
and user experience.
Device Information (1)
PART NUMBER
TSC2013-Q1
(1)
PACKAGE
BODY SIZE (NOM)
PVQFN (16)
4.00 mm × 4.00 mm
TSSOP (16)
4.40 mm × 5.00 mm
For all available packages, see the orderable addendum at
the end of the datasheet.
Block Diagram
PENIRQ
SNSVDD/
VREF
PINTDAV
X+
X±
Y+
Touch Screen
Driver
Interface
MUX
SAR
ADC
Y±
Pre-Processing
DAV
SCL
2
I C Serial
Interface and
Control
SDA
AD0
AD1
AUX
Internal
Clock
SNSGND
RESET
R(SENSE)
AGND
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Table of Contents
1
2
3
4
5
6
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configurations and Functions .......................
Specifications.........................................................
6.1
6.2
6.3
6.4
6.5
6.6
1
1
1
2
3
4
Absolute Maximum Ratings ..................................... 4
Handling Ratings....................................................... 4
Recommended Operating Conditions....................... 4
Thermal Information .................................................. 4
Electrical Characteristics........................................... 5
Timing Requirements — I2C Standard Mode (ƒ(SCL) =
100 kHz) .................................................................... 7
6.7 Timing Requirements — I2C Fast Mode (ƒ(SCL) = 400
kHz) ........................................................................... 7
6.8 Timing Requirements — I2C High-Speed Mode
(ƒ(SCL) = 1.7 MHz) ...................................................... 8
6.9 Timing Requirements — I2C High-Speed Mode
(ƒ(SCL) = 3.4 MHz) ..................................................... 8
6.10 Typical Characteristics .......................................... 10
7
Detailed Description ............................................ 12
7.1
7.2
7.3
7.4
7.5
7.6
8
Overview .................................................................
Functional Block Diagram .......................................
Feature Description.................................................
Device Functional Modes........................................
Programming...........................................................
Register Maps .........................................................
12
13
14
23
29
41
Application and Implementation ........................ 51
8.1 Application Information............................................ 51
8.2 Typical Application ................................................. 52
9 Power Supply Recommendations...................... 60
10 Layout................................................................... 60
10.1 Layout Guidelines ................................................. 60
10.2 Layout Example .................................................... 61
11 Device and Documentation Support ................. 61
11.1 Trademarks ........................................................... 61
11.2 Electrostatic Discharge Caution ............................ 61
11.3 Glossary ................................................................ 61
12 Mechanical, Packaging, and Orderable
Information ........................................................... 61
4 Revision History
Changes from Original (June 2014) to Revision A
Page
•
Released full version of data sheet ....................................................................................................................................... 1
•
Changed device status from Product Preview to Production Data ....................................................................................... 1
2
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
5 Pin Configurations and Functions
16-Pin TSSOP
PW Package
Top View
AD0
1
16
SNSGND
SDA
2
15
Y–
SCL
3
14
X–
AD1
4
13
Y+
PINTDAV
5
12
X+
RESET
6
11
SNSVDD/VREF
DGND
7
10
AGND
I/OVDD
8
9
AGND
SNSVDD/VREF
9
10
12
11
X+
Y+
16-Pin VQFN With Thermal Pad
RSA Package
Top View
DGND
AD0 16
5
RESET
4
6
PINTDAV
SNSGND 15
3
I/OVDD
AD1
7
2
Y– 14
SCL
AUX
1
8
SDA
X– 13
AUX
Pin Functions
PIN
I/O
ADC
1
I
D
I2C bus TSC address input bit 0
3
4
I
D
I2C bus TSC address input bit 1
AGND
9
10
—
—
Analog, digital, and ESD ground (1)
AUX
8
9
—
A
Auxiliary channel
DGND
6
7
—
—
No internal connection. Connect this pin to analog ground for mechanical
stability.
I/OVDD
7
8
I
—
Digital interface voltage
PINTDAV
4
5
O
D
Interrupt output. Data available or the pen-detect interrupt (PENIRQ),
depending on setting. Pin polarity is active-low.
RESET
5
6
I
D
External hardware reset input (active-low).
SDA
1
2
I/O
D
Serial data I/O
SCL
2
3
I
D
Serial clock
SNSGND
15
16
—
—
Sensor driver return
SNSVDD/VREF
10
11
I
—
Power supply for sensor drivers and other analog blocks
X+
11
12
—
A
X+ channel
X–
13
14
—
A
X– channel
Y+
12
13
—
A
Y+ channel
Y–
14
15
—
A
Y– channel
NAME
RSA
PW
AD0
16
AD1
(1)
DESCRIPTION
For optimized system IEC ESD performance, contact Texas Instruments for schematic and layout reviews and suggestions.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
3
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings (1)
Over operating free-air temperature range (unless otherwise noted).
MIN
MAX
UNIT
Analog input X+, Y+, AUX to SNSGND
–0.4
SNSVDD + 0.1
V
Analog input X–, Y– to SNSGND
–0.4
SNSVDD + 0.1
V
SNSVDD to SNSGND
–0.3
5
V
SNSVDD to AGND
–0.3
5
V
I/OVDD to AGND
–0.3
5
V
SNSVDD to I/OVDD
–2.4
0.3
V
Digital input voltage to AGND
–0.3
I/OVDD + 0.3
V
Digital output voltage to AGND
–0.3
I/OVDD + 0.3
V
Voltage
Power dissipation
(TJmax – TA) / RθJA
Operating free-air temperature range, TA
–40
Junction temperature, TJmax
(1)
125
°C
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated is not implied. Exposure to absolutemaximum rated conditions for extended periods may affect device reliability.
6.2 Handling Ratings
Tstg
MIN
MAX
UNIT
–65
150
°C
(1)
–2000
2000
Corner pins (RSA: 1, 4, 5,
8, 9, 12, 13, and 16;
PW: 1, 8, 9, and 16)
–750
750
Other pins
Storage temperature range
Human body model (HBM), per AEC Q100-002
V(ESD)
(1)
(2)
Electrostatic discharge
Charged device model (CDM),
per AEC Q100-011
V
–500
500
IEC contact discharge (2)
X+, X–, Y+, Y–
–15
15
kV
IEC air discharge (2)
X+, X–, Y+, Y–
–25
25
kV
AEC Q100-002 indicates HBM stressing is done in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
Test method based on IEC standard 61000-4-2. Contact Texas Instruments for test details.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
Input voltage SNSVDD/VR
1.6
3.3
3.6
UNIT
V
Input voltage I/OVDD
1.2
3.3
3.6
V
6.4 Thermal Information
THERMAL METRIC (1)
RSA
PW
16 PINS
16 PINS
UNIT
RθJA
Junction-to-ambient thermal resistance
33.7
100.9
°C/W
RθJC(top)
Junction-to-case(top) thermal resistance
36.7
36.1
°C/W
RθJB
Junction-to-board thermal resistance
10.5
45.7
°C/W
ψJT
Junction-to-top characterization parameter
0.6
2.6
°C/W
ψJB
Junction-to-board characterization parameter
10.5
45.1
°C/W
RθJC(bot)
Junction-to-case(bottom) thermal resistance
2.5
—
°C/W
(1)
4
For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
6.5 Electrical Characteristics
At TA = –40°C to 125°C, V(SNSVDD/VREF) = 1.6 V to 3.6 V, and V(I/OVDD) (1) = 1.2 V to V(SNSVDD/VREF), unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
AUXILIARY ANALOG INPUT
Input voltage
0
Input capacitance
Vref
12
V
pF
–1
1
μA
Input leakage current
No ADC conversion
Full-scale average input current
V(SNSVDD/VREF) = 1.6 V, continuous AUX, ƒ(ADC) = 2 MHz
Resolution
Programmable: 10 or 12 bits
No missing codes
12-bit resolution
11
Integral linearity
12-bit resolution mode, ƒ(ADC) = 2 MHz
–3
Differential linearity
12-bit resolution mode, fADC = 2MHz
–2
Offset error
V(SNSVDD/VREF) = 1.6 V, 12-bit mode, ƒ(ADC) = 2 MHz, filter off
0.2
LSB
Gain error
V(SNSVDD/VREF) = 1.6 V, 12-bit mode, ƒ(ADC) = 2 MHz, filter off
2
LSB
μA
2
ADC
Data format
12
Bits
–0.5 to 0.5
3
LSB (2)
–0.5 to 0.5
4
LSB
Bits
Straight binary
REFERENCE INPUT
Vref range
1.6
SNSVDD/VREF input-current drain
Continuous AUX mode, V(SNSVDD/VREF) = 1.6 V, ƒ(ADC) = 2 MHz
Input impedance
No ADC conversion
V(SNSVDD/VREF)
V
5
μA
> 100
MΩ
TOUCH SENSORS
X+ 50-kΩ pullup resistor, R(IRQ)
52
kΩ
Y+, X+
TA = 25°C, V(SNSVDD/VREF) = 1.6 V
7
Ω
Y–, X–
TA = 25°C, V(SNSVDD/VREF) = 1.6 V
5
Switch on-resistance
Switch drivers drive current
100-ms duration
Ω
50
mA
4.3
MHz
INTERNAL OSCILLATOR
ƒ(OSC)
Clock frequency
V(SNSVDD/VREF) = 1.6 V, TA = 25°C
3.3
V(SNSVDD/VREF) = 3 V, TA = 25°C
Frequency drift
3.7
3.8
MHz
V(SNSVDD/VREF) = 1.6 V
–0.008
%/°C
V(SNSVDD/VREF) = 3 V
–0.021
%/°C
DIGITAL INPUT/OUTPUT
Logic family
CMOS
VIH
Input-voltage logic-level high
1.2 V ≤ V(I/OVDD) < 3 V
VIL
Input-voltage logic-level low
1.2 V ≤ V(I/OVDD) < 3 V
IIL, IIH
Input-current logic-level low and high
CI
Input-capacitance logic level
VOH
Output-voltage logic-level high
IOH = 100 μA
VOL
Output-voltage logic-level low
IOL = –3.2 mA
Ilkg
Leakage-current logic level
SDA
CO
Output-capacitance logic level
SDA
0.7 ×
V(I/OVDD)
3.6
V
–0.3
0.2 × V(I/OVDD)
V
–1
1
μA
10
pF
V(I/OVDD)
– 0.2
V(I/OVDD)
V
0
0.2
V
–1
1
μA
10
pF
POWER-SUPPLY REQUIREMENTS
Power-supply voltage
(1)
(2)
SNSVDD
1.6
3
V
I/OVDD (1)
1.2
V(SNSVDD/VREF)
V
I/OVDD must be ≤ SNSVDD.
LSB means least-significant bit. With SNSVDD/VREF= 2.5 V, one LSB is 610 μV.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
5
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Electrical Characteristics (continued)
At TA = –40°C to 125°C, V(SNSVDD/VREF) = 1.6 V to 3.6 V, and V(I/OVDD)(1) = 1.2 V to V(SNSVDD/VREF), unless otherwise noted.
PARAMETER
TEST CONDITIONS
TYP
MAX
UNIT
V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V
420
570
μA
TA = 25°C, filter on, M = 15, W = 7, PSM = 1,
C[3:0] = (0, 0, 0, 0), RM = 1, CL[1:0] = (0, 1),
BTD[2:0] = (1, 0, 1), 50 SSPS, MAVEX =
MAVEY = MAVEZ = 1, ƒ(ADC) = 2 MHz, sensor
drivers supply included (5)
V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V
200
μA
V(SNSVDD/VREF) = V(I/OVDD) = 3 V
400
μA
TA = 25°C, filter off, M = W = 1, PSM = 1,
C[3:0] = (0, 0, 0, 0), RM = 1, CL[1:0] = (0, 1),
BTD[2:0] = (1, 0, 1), 50 SSPS, MAVEX =
MAVEY = MAVEZ = 1, ƒ(ADC) = 2 MHz, sensor
drivers supply included (5)
V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V
180
μA
V(SNSVDD/VREF) = V(I/OVDD) = 3 V
370
μA
V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V,
approximately 28 kSPS effective
rate
190
μA
V(SNSVDD/VREF) = V(I/OVDD) = 3 V,
approximately 28.4 kSPS
effective rate
370
μA
V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V,
approximately 10.5 kSPS
effective rate
355
μA
V(SNSVDD/VREF) = V(I/OVDD) = 3 V,
approximately 10.9 kSPS
effective rate
655
μA
V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V,
approximately 1.17 kSPS
effective rate
36.2
μA
V(SNSVDD/VREF) = V(I/OVDD) = 3 V,
approximately 1.17 kSPS
effective rate
64.9
μA
TA = 25°C, filter off, M = W = 1, C[3:0] = (1, 0,
0, 0), RM = 1, CL[1:0] = (0, 1), cont AUX
mode, ƒ(ADC) = 2 MHz, without reading data
register
Quiescent supply
current (3) (4)
TA = 25°C, filter off, M = W = 1, C[3:0] = (0, 1,
0, 1), RM = 1, CL[1:0] = (0, 1), non-cont AUX
mode, ƒ(ADC) = 2 MHz, high-speed mode
TA = 25°C, filter on, M = 7, W = 3, C[3:0] = (0,
1, 0, 1), RM = 1, CL[1:0] = (0, 1), MAVEAUX
= 1, non-cont AUX mode, ƒ(ADC) = 2 MHz,
high-speed mode, full speed
TA = 25°C, filter on, M = 7, W = 3, C[3:0] = (0,
1, 0, 1), RM = 1, CL[1:0] = (0, 1), MAVEAUX
= 1, non-cont AUX mode, ƒ(ADC) = 2 MHz,
high-speed mode, reduced speed (8.2-kSPS
equivalent rate)
(3)
(4)
(5)
6
MIN
Power-down supply current
TA = 25°C, not addressed, SCL = SDA = 1, RESET = 1,
PINTDAV = 1, V(SNSVDD/VREF) = I/OVDD = Vref = 1.6 V
0.04
0.8
μA
Digital power-down supply current
TA = 25°C, not addressed, SCL = SDA = 1, RESET = 1,
PINTDAV = 1, V(SNSVDD/VREF) = V(I/OVDD) = Vref = 1.6 V
0.04
0.8
μA
Supply current from SNSVDD.
For detailed information on test condition parameter and bit settings, see the section.
Touch sensor modeled by 2 kΩ for X– plane and Y– plane, and 1 kΩ for Z-plane (touch resistance).
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
6.6 Timing Requirements — I2C Standard Mode (ƒ(SCL) = 100 kHz)
All specifications typical at –40°C to 125°C, V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V to 3 V, unless otherwise noted.
MIN
t(WL_RESET)
Reset low time (1)
ƒ(SCL)
SCL clock frequency
t(BUF)
Bus free time between a STOP and START
condition
th(STA)
Hold time for (repeated) START condition
t(LOW)
Low period of SCL clock
t(HIGH)
High period of the SCL clock
tsu(STA)
Setup time for a repeated START condition
th(DAT)
Data hold time
tsu(DAT)
Data setup time
tr
Rise time of both SDA and SCL signals
tf
Fall time of both SDA and SCL signals
C(b) = total bus capacitance
See Figure 1
tsu(STO)
Setup time for STOP condition
See Figure 1
C(b)
Capacitive load for each bus line
C(b) = total capacitance of one bus line in pF
td(SP)
Pulse duration of spikes that must be
suppressed by the input filter
(1)
See Figure 1 and Figure 37
See Figure 1
MAX
UNIT
100
kHz
μs
10
4.7
μs
4
μs
4.7
μs
4
μs
μs
4.7
0
3.45
250
μs
ns
1000
300
ns
ns
μs
4
N/A
400
pF
N/A
ns
MAX
UNIT
400
kHz
V(SNSVDD/VREF) ≥ 1.6 V
6.7 Timing Requirements — I2C Fast Mode (ƒ(SCL) = 400 kHz)
All specifications typical at –40°C to 125°C, V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V to 3 V, unless otherwise noted.
MIN
t(WL_RESET)
Reset low time (1)
ƒ(SCL)
SCL clock frequency
t(BUF)
Bus free time between a STOP and START
condition
1.3
μs
th(STA)
Hold time for (repeated) START condition
0.6
μs
t(LOW)
Low period of SCL clock
1.3
μs
0.6
μs
See Figure 1 and Figure 37
See Figure 1
t(HIGH)
High period of the SCL clock
tsu(STA)
Setup time for a repeated START condition
th(DAT)
Data hold time
tsu(DAT)
Data setup time
tr
Rise time of both SDA and SCL signals
tf
Fall time of both SDA and SCL signals (2)
C(b) = total bus capacitance
See Figure 1
tsu(STO)
Setup time for STOP condition
See Figure 1
C(b)
Capacitive load for each bus line
C(b) = total capacitance of one bus line in pF
td(SP)
Pulse duration of spikes that must be
suppressed by the input filter
(1)
(2)
μs
10
μs
0.6
0
0.9
100
ns
20 + 0.1 × C(b)
300
20 + 0.1 × C(b)
300
ns
ns
μs
0.6
0
μs
400
pF
50
ns
V(SNSVDD/VREF) ≥ 1.6 V
C(b) = the total capacitance of one bus line in pF. If using both fast-mode and Hs-mode devices, one may use faster fall times according
to the Timing Requirements — I2C High-Speed Mode (ƒ(SCL) = 3.4 MHz) section. Note that the TSC2013-Q1 device is an Hs-mode
device and follows the table requirements listed in the Timing Requirements — I2C High-Speed Mode (ƒ(SCL) = 3.4 MHz) section.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
7
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
6.8 Timing Requirements — I2C High-Speed Mode (ƒ(SCL) = 1.7 MHz)
All specifications typical at –40°C to 125°C, V(SNSVDD/VREF) = V(I/OVDD) = to 3 V, unless otherwise noted.
MIN
MAX
UNIT
1.7
MHz
t(WL_RESET)
Reset low time (1)
ƒ(SCL)
SCL clock frequency
th(STA)
Hold time of (repeated) START condition
160
ns
t(LOW)
Low period of SCL clock
320
ns
t(HIGH)
High period of the SCL clock
120
ns
tsu(STA)
Setup time for a repeated START condition
th(DAT)
Data hold time
0
tsu(DAT)
Data setup time
10
tr(CL)
Rise time of SCL signal
20
80
ns
tr(DA)
Rise time of SDA signal
20
160
ns
20
80
ns
1
160
ns
20
160
ns
400
pF
10
ns
See Figure 2 and Figure 37
See Figure 2
160
(2)
tf(CL)
Fall time of SCL signal
tf(DA)
Fall time of SDA signal
tr(CL1)
Rise time of SCL signal after a repeated START
condition and after an acknowledge bit
tsu(STO)
Setup time for STOP condition
See Figure 2
C(b)
Capacitive load for each bus line
C(b) = total capacitance of one bus line in pF
td(SP)
Pulse duration of spikes that must be
suppressed by the input filter
(1)
(2)
C(b) = total bus capacitance
Figure 2
μs
10
ns
150
ns
160
0
ns
ns
V(SNSVDD/VREF) ≥ 1.6 V
For capacitive bus loads between 100 pF and 400 pF, interpolate the rise-time and fall-time values linearly.
6.9 Timing Requirements — I2C High-Speed Mode (ƒ(SCL) = 3.4 MHz)
All specifications typical at –40°C to 125°C, V(SNSVDD/VREF) = V(I/OVDD) = 1.6 V (1) to 3 V, unless otherwise noted.
MIN
MAX
UNIT
3.4
MHz
t(WL_RESET)
Reset low time (2)
ƒ(SCL)
SCL clock frequency
th(STA)
Hold time for (repeated) START condition
160
ns
t(LOW)
Low period of SCL clock
160
ns
t(HIGH)
High period of the SCL clock
60
ns
tsu(STA)
Setup time for a repeated START condition
th(DAT)
Data hold time
0
tsu(DAT)
Data setup time
10
tr(CL)
Rise time of SCL signal
10
40
ns
tr(DA)
Rise time of SDA signal
10
80
ns
tf(CL)
Fall time of SCL signal
10
40
ns
tf(DA)
Fall time of SDA signal
1
80
ns
tr(CL1)
Rise time of SCL signal after a repeated START
condition and after an acknowledge bit
10
80
ns
tsu(STO)
Setup time for STOP condition
See Figure 2
C(b)
Capacitive load for each bus line
C(b) = total capacitance of one bus line in pF
100
pF
td(SP)
Pulse duration of spikes that must be
suppressed by the input filter
10
ns
(1)
(2)
(3)
8
See Figure 2 and Figure 37
See Figure 2
C(b) = total bus capacitance (3)
See Figure 2
μs
10
160
ns
70
ns
160
0
ns
ns
Because of the low supply voltage of 1.2 V and the wide temperature range of –40°C to 125°C, the I2C system devices may not reach
the maximum specification of I2C high-speed mode, and ƒ(SCL) may not reach 3.4 MHz.
V(SNSVDD/VREF) ≥ 1.6 V
Capacitive load from 10 pF to 100 pF.
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
S
Sr
P
S
SDA
tsu(STA)
tsu(DAT)
t(BUF)
th(STA)
th(DAT)
t(LOW)
SCL
tsu(STO)
t(HIGH)
th(STA)
tr
tf
S = START Condition
Sr = Repeated START Condition
P = STOP Condition
= Resistor Pull Up
Figure 1. Detailed I/O Timing for Standard and Fast Modes
Sr
Sr
P
tf(DA)
tr(DA)
SDA
th(DAT)
tsu(STA)
th(STA)
tsu(STO)
tsu(DAT)
SCL
tf(CL)
tr(CL1)(1)
tr(CL1)(1)
tr(CL)
t(HIGH)
t(LOW)
t(LOW)
t(HIGH)
= Current Source Pull Up
= Resistor Pull Up
(1)
Sr = Repeated START Condition
P = STOP Condition
The First rising edge of the SCL signal after Sr and after each acknowledge bit.
Figure 2. Detailed I/O Timing for High-Speed Mode
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
9
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
6.10 Typical Characteristics
At TA = –40°C to 125°C, SNSVDD/VREF = 1.6 V to 3 V, I/OVDD = 1.2 V to SNSVDD/VREF, ƒ(ADC) = ƒ(OSC) / 2, high-speed
mode (ƒ(SCL) = 3.4 MHz), 12-bit mode, and non-continuous AUX measurement, unless otherwise noted.
1.5
1.5
V(I/OVDD) = 1.2 V
V(SNSVDD) = 1.6 V
V(I/OVDD) = 1.6 V
1
Delta from 25°C (LSB)
Delta from 25°C (LSB)
1
V(SNSVDD) = 1.2 V
V(SNSVDD) = 3 V
0.5
0
–0.5
V(I/OVDD) = 3 V
0.5
0
–0.5
–1
–1
–1.5
–40
–20
0
20
40
Temperature (°C)
60
80
–1.5
–40
100
Figure 3. Change in Offset vs Temperature
20
40
Temperature (°C)
60
80
100
Figure 4. Change in Gain vs Temperature
400
350
300
250
200
150
V(SNSVDD) = 1.6 V
100
SNSVDD Supply Current (mA)
SNSVDD Supply Current (mA)
0
0.6
450
V(SNSVDD) = 3 V
50
-40
M=1
-20
0
20
40
Temperature (°C)
W = 1 (See Table 1)
AUX non-continuous mode
60
80
0.5
ƒ(ADC) = 1 MHZ
ƒ(SAMPLE) = 23 kHz
0.4
ƒ(ADC) = 2 MHZ
ƒ(SAMPLE) = 28 kHz
0.3
0.2
0.1
0
1.2
100
ƒ(SAMPLE) = 28 kHz
1.6
2.0
2.4
2.8
Supply Voltage (V)
3.2
3.6
TA = 25° C
Figure 5. SNSVDD Supply Current vs Temperature
Figure 6. SNSVDD Supply Current vs SNSVDD Supply
Voltage
1400
0.7
M = 5, W = 7
M = 1, W = 1
0.6
Power-Down SNSVDD Current (nA)
SNSVDD Supply Current (mA)
–20
0.5
0.4
0.3
0.2
0.1
V(SNSVDD) = 1.6 V
1200
V(SNSVDD) = 3 V
1000
800
600
400
200
0
0
1.2
1.6
2.0
2.4
2.8
Supply Voltage (V)
3.2
3.6
-40
-20
0
20
40
Temperature (°C)
60
80
100
t(PVS), t(PRE), t(SNS) = default values
TSC-initiated mode scan X, Y, and Z at 50SSPS
Touch sensor modeled by: 2 kΩ for X-plane and Y-plane and 1 kΩ
for Z (touch resistance, See Figure 14)
Figure 7. Supply Current vs Supply Voltage, TA = 25° C
10
Submit Documentation Feedback
Figure 8. Power-Down Supply Current vs Temperature
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Typical Characteristics (continued)
At TA = –40°C to 125°C, SNSVDD/VREF = 1.6 V to 3 V, I/OVDD = 1.2 V to SNSVDD/VREF, ƒ(ADC) = ƒ(OSC) / 2, high-speed
mode (ƒ(SCL) = 3.4 MHz), 12-bit mode, and non-continuous AUX measurement, unless otherwise noted.
45
80
60
SNSVDD
40
20
V(I/OVDD) = 1.6 V
35
V(I/OVDD) = 3 V
30
25
20
15
10
5
0
0
1.2
1.6
2.0
2.4
2.8
Supply Voltage (V)
3.2
–40
3.6
TA = 25°C
–20
0
20
40
Temperature (°C)
60
80
100
I/OVDD = SNSVDD/VREF
Figure 9. Power-Down Supply Current vs Supply Voltage
Figure 10. I/OVDD Supply Current vs Temperature
60
10
Reference Input Current (mA)
I/OVDD Supply Current (µA)
V(I/OVDD) = 1.2 V
40
I/OVDD Supply Current (µA)
Power-Down SNSVDD Current (nA)
100
50
40
30
20
10
0
8
6
4
2
V(SNSVDD) = 1.6 V
V(SNSVDD) = 3 V
0
1.2
1.6
2.0
2.4
Voltage (V)
2.8
IOVDD = SNSVDD/VREF
3.2
3.6
-40
ƒ(SAMPLE) = 28 kHz
-20
0
20
40
Temperature (°C)
IOVDD = SNSVDD/VREF
Figure 11. I/OVDD Supply Current vs I/OVDD Supply Voltage
60
80
100
AUX continuous mode
Figure 12. Reference Input Current vs Temperature
Reference Input Current (µA)
14
12
10
8
6
4
2
0
1.2
1.6
IOVDD = SNSVDD/VREF
TA = 25°C
2.0
2.4
Voltage (V)
2.8
3.2
3.6
AUX continuous mode
Figure 13. Reference Input Current vs SNSVDD Supply Voltage
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
11
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7 Detailed Description
7.1 Overview
The TSC2013-Q1 device is an analog interface circuit for a human-interface touch-screen device. A registerbased architecture eases integration with microprocessor-based systems through a standard I2C bus. Registers
and onboard state machines control all peripheral functions. The TSC2013-Q1 features include:
• Very low-power touch-screen controller
• Very small onboard footprint
• Flexible preprocessing which relieves the host from tedious routine tasks and saves resources for more
critical tasks
• Ability to work on very low supply voltage
• Minimal connection interface allows easiest isolation and reduces the number of dedicated I/O pins required
• Enhanced ESD protection
• Panel-current sensing
• Miniature device, yet complete; requires no external supporting components
NOTE
Although the TSC2013-Q1 device can use an external reference, the SNSVDD/VREF pin
can also be used as the reference.
The TSC2013-Q1 device consists of the following blocks (see the Functional Block Diagram section):
• Touch-screen interface
• Auxiliary input (AUX)
• Acquisition-activity preprocessing
• Internal conversion clock
• I2C interface
Communication with the TSC2013-Q1 device is through an I2C serial interface. The TSC2013-Q1 device is an
I2C slave device. Therefore, data shifts into or out of the TSC2013-Q1 device under the control of the host
microprocessor, which also provides the serial data clock.
Writing to different registers in the TSC2013-Q1 device controls the TSC2013-Q1 device and device functions.
The use of a simple command protocol (compatible with I2C) addresses these registers. This protocol can be an
I2C write-address followed by multiple control bytes, or multiple combinations of control and data bytes for writing
into different registers (two bytes each). To read from registers, write an I2C read-address to the TSC2013-Q1
device, followed by one or multiple sequential reads from the registers.
The host writes the address of the register to be read in control byte 0 with the register address and read-bit (as
described in the previous paragraph). The register address serves as a pointer to the register map where the first
read starts. This designated register address is static and a write to a register address does not need to occur
again unless a new register address has overwritten it or after a TSC2013-Q1 reset (by a software reset or by
the RESET pin).
The touch-measurement result goes into the TSC2013-Q1 registers, from which the host may read it at any time.
This preprocessing frees up the host in order to allocate resources to more-critical tasks. Two optional signals
are also available from the TSC2013-Q1 device to indicate that data are available for the host to read. The
PINTDAV pin is a programmable interrupt or status output pin. With the PINTDAV pin programmed as a DAV
output, the pin indicates that an ADC conversion has completed and that data are available. With the PINTDAV
pin programmed as a PENIRQ output, the pin indicates the detection of a touch on the touch screen. The status
register of the TSC2013-Q1 device provides an extended status reading, including the state of the DAV and
PENIRQ outputs, without the cost of any dedicated pin. See Figure 14 for a typical application of the TSC2013Q1 device.
To detect two touches, add an external R(SENSE) resistor as shown in Figure 14. The value of R(SENSE) depends
on the touch-panel resistance. The ratio between the lowest touch-panel resistance and R(SENSE) should be
approximately 4.5.
12
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Overview (continued)
1.6 VDC
1 µF
0.1 µF
1.6 VDC
AGND
Y+
I/OVDD
SNSVDD/VREF
X+
1.2 kΩ
PINTDAV
GPIO
SDA
TSC2013-Q1
SDA
AD1
AD0
AUX
AGND
Y–
SNSGND
SCL
Touch
Screen
Host
Processor
GPIO
RESET
X–
1.2 kΩ
SCL
(PINTDAV is optional;
software implementation
polling of the Status register is
possible)
AGND
R(SENSE)
47 Ω
Figure 14. Typical Circuit Configuration
7.2 Functional Block Diagram
PENIRQ
SNSVDD/
VREF
PINTDAV
X+
X±
Y+
Touch Screen
Driver
Interface
MUX
SAR
ADC
Y±
Pre-Processing
DAV
SCL
2
I C Serial
Interface and
Control
SDA
AD0
AD1
AUX
Internal
Clock
SNSGND
RESET
R(SENSE)
AGND
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
13
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.3 Feature Description
7.3.1 Touch-Screen Operation
A resistive touch screen operates by applying a voltage across a resistor network and measuring the change in
resistance at a given point on the matrix where an input (stylus, pen, or finger) touches the screen. The change
in the resistance ratio marks the location on the touch screen.
The TSC2013-Q1 device supports resistive 4-wire configurations as shown in Figure 15. The circuit determines
location in two coordinate-pair dimensions, although addition of a third dimension for measuring pressure is
possible.
7.3.2 4-Wire Touch Screen Measurements
Figure 15 shows construction of a typical four-wire touch screen. The screen consists of two transparent resistive
layers separated by insulating spacers.
Conductive Bar
Transparent Conductor (ITO)
Bottom Side
Y+
Transparent
Conductor (ITO)
Top Side
X+
Silver
Ink
XY-
ITO = Indium Tin Oxide
Insulating Material (Glass)
Figure 15. Four-Wire Touch Screen Construction
The four-wire touch-screen panel works by applying a voltage across the vertical or horizontal resistive network.
To determine a touch location, the TSC2013-Q1 device provides a set of eight data measurements (X1, X2, IX,
Y1, Y2, IY, Z1, and Z2). Figure 17 through Figure 19 show the internal ADC configurations. Taking an X1
measurement involves activating the X+ and X– drivers and digitizing the voltage at Y+. The R(SENSE) resistor
must be connected as shown in Figure 14. The SNSGND and AUX pins connect to one end of R(SENSE), and the
other end connects to the AGND pin.
The TSC2013-Q1 device can also measure touch pressure (Z). To determine a pen or finger touch,
determination of the pressure of the touch is required. Generally, having very high performance for this test is not
necessary. Therefore, TI recommends 10-bit resolution mode. Several different ways of performing this
measurement are available. The TSC2013-Q1 device supports two methods. The first method requires knowing
the X-plate resistance, the measurement of X1, and two additional cross-panel measurements (Z2 and Z1) of the
touch screen (see Figure 16). Equation 1 calculates the touch resistance (R(TOUCH)).
X1
§ Z2 ·
R(TOUCH) R X(PLATE) u
u
1
4096 ¨© Z1 ¸¹
(1)
The second method requires knowing both the X-plate and Y-plate resistance, and the measurement of X1, Y1,
and Z1. Equation 2 also calculates the touch resistance.
R X(PLATE) § 4096 ·
Y1 ·
§
R(TOUCH)
1¸ R Y(PLATE) u ¨ 1
¸
4096 ¨© Z1
¹
© 4096 ¹
(2)
14
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Feature Description (continued)
Measure X1
X+
Y+
Touch
X1-Position
Y–
X–
Measure Z1-Position
Y+
X+
Touch
Z1-Position
X–
Y–
Y+
X+
Touch
Z2-Position
X–
Y–
Measure Z2-Position
Figure 16. Pressure Measurement
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
15
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Feature Description (continued)
X1 Measurement
X2 Measurement
X+
Y+
+IN
X+
+REF
Y-
+IN
Converter
+REF
Converter
-IN
-IN
-REF
-REF
X–
X–
X+, X– drivers are On
X+, X– drivers are On
IX Measurement
VREF
AUX
+IN
+REF
Converter
-IN
-REF
AGND
X+, X– drivers are On
Figure 17. X-Coordinate Differential-Triplet Measurement (X1, X2, IX)
16
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Feature Description (continued)
Y1 Measurement
Y2 Measurement
Y+
X+
+IN
Y+
+REF
X-
+IN
Converter
+REF
Converter
-IN
-IN
-REF
-REF
Y-
Y-
Y+, Y– drivers are On
Y+, Y– drivers are On
IY Measurement
VREF
AUX
+IN
+REF
Converter
-IN
-REF
AGND
Y+, Y– drivers are On
Figure 18. Y-Coordinate-Differential-Triplet Measurement (Y1, Y2, IY)
Z1 Measurement
Z2 Measurement
Y+
X+
+IN
+REF
Y+
Y-
+IN
Converter
-IN
+REF
Converter
-IN
-REF
-REF
X–
X–
X–, Y+ drivers are On
X–, Y+ drivers are On
Figure 19. Z-Measurement (Z1, Z2)
When touching or pressing the touch panel with the drivers to the panel turned on, the voltage across the touch
panel often overshoots and then slowly settles down (decays) to a stable DC value. This effect is a result of
mechanical bouncing caused by vibration of the top-layer sheet of the touch panel when pressing the panel.
Without accounting for this settling time, the converted value is in error. Therefore, introducing a delay between
the time the driver for a particular measurement is turned on and the time a measurement is made is necessary.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
17
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Feature Description (continued)
In some applications, external capacitors may be required across the touch screen for filtering noise picked up by
the touch screen (such as noise generated by the LCD panel or back-light circuitry). The value of these
capacitors provides a low-pass filter to reduce noise, but causes an additional settling-time requirement when the
panel is touched.
The TSC2013-Q1 device offers several solutions to this problem. A programmable delay time is available that
sets the delay between turning the drivers on and making a conversion. The TSC2013-Q1 device uses this
delay, referred to as the panel voltage-stabilization time, in some of the device modes. In other modes,
commands can cause the TSC2013-Q1 device to turn on the drivers only without performing a conversion.
Issuing the command to perform a conversion occurs after allowing sufficient stabilization time.
The TSC2013-Q1 touch-screen interface can measure different data sets. Determination of these measurements
is possible under three different modes of the ADC:
• TSMode1: conversion controlled by the TSC2013-Q1 device and initiated by the touchscreen controller (TSC)
• TSMode2: conversion controlled by the TSC2013-Q1 device and initiated by the host responding to the
PENIRQ signal
• TSMode3: conversion completely controlled by the host processor
7.3.3 Analog-to-Digital Converter
Figure 20 shows the analog inputs of the TSC2013-Q1 device. A multipexer provides the analog inputs (X, Y,
and Z touch panel coordinates and auxiliary inputs) to the successive-approximation register (SAR) analog-todigital converter (ADC). The basis of ADC architecture is capacitive redistribution architecture, which inherently
includes a sample-and-hold function.
SNSVDD/VREF
PINTDAV
SNSVDD
R(IRQ)(1)
50 kΩ
Level Shift
Data
Available
Pen Touch
Control
Logic
Preprocessing
Zone
Detect
MAV
SNSVDD
C3-C0
X+
X–
SNSVDD
Y+
+IN
Y–
+REF
Converter
–IN
–REF
SNSGND
AUX
AGND
R(SENSE)
(1)
Untrimmed resistor; see the typical value in the table.
Figure 20. Simplified Diagram of the Analog Input Section
18
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Feature Description (continued)
A unique configuration of low on-resistance switches allows an unselected ADC input channel to provide power
and an accompanying pin to provide ground for driving the touch panel. By maintaining a differential input to the
converter and a differential reference input architecture, negating errors caused by the on-resistance of the driver
switches is possible.
Two ADC-control registers control the ADC. Several modes of operation are possible, depending on the bits set
in the control registers. Programming of channel selection, scan operation, preprocessing, resolution, and
conversion rate is through these registers. The following sections outline these modes for each type of analog
input. The appropriate result register stores the conversion results.
7.3.3.1 Data Format
The TSC2013-Q1 output data are in straight binary format as shown in Figure 21. Figure 21 shows the ideal
output code for the given input voltage and does not include the effects of offset, gain, or noise.
VFS = Full-Scale Voltage = Vref(1)
1 LSB = Vref(1) / 4096
1 LSB
11...111
Output Code
11...110
11...101
00...010
00...001
00...000
0V
Input Voltage
(2)
FS - 1 LSB
(V)
(1)
Reference voltage at converter: +REF – (–REF). See Figure 20.
(2)
Input voltage at converter, after multiplexer: +IN – (–IN). See Figure 20.
Figure 21. Ideal Input Voltages and Output Codes
7.3.3.2 Reference
The TSC2013-Q1 device uses an external voltage reference applied to the SNSVDD/VREF pin. Using the
SNSVDD/VREF pin as the reference voltage is possible because the upper reference voltage range is the same
as the supply-voltage range.
7.3.3.3 Variable Resolution
The TSC2013-Q1 device provides either 10-bit or 12-bit resolution for the ADC. Lower resolution is often
practical for measuring slow-changing signals such as touch pressure. Performing the conversions at lower
resolution reduces the amount of time required for the ADC to complete the conversion process which also
lowers power consumption.
7.3.3.4 Conversion Clock and Conversion Time
The TSC2013-Q1 device contains an internal clock (oscillator) that drives the internal state machines that
perform the many functions of the part. This clock is divided down to provide a conversion clock for the ADC.
The setting for the division ratio of this clock is in the ADC control register (see Configuration Register 0 (address
= 0) [reset = 4000h for read; 0000h for write]). The ability to change the conversion clock rate allows the user to
select the optimal values for resolution, speed, and power dissipation. Using the 4-MHz (oscillator) clock directly
as the ADC clock (when the CL[1:0] bit is set to 0) limits the ADC resolution to 10 bits. Using higher resolutions
at this speed does not result in more accurate conversions. Twelve-bit resolution requires that the CL bits 1 and
0 are set to 0 and 1, or 1 and 0 (respectively).
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
19
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Feature Description (continued)
Regardless of the conversion clock speed, the internal clock runs nominally at 3.8 MHz at a 3-V supply
(SNSVDD) and slows down to 3.6 MHz at a 1.6-V supply. The conversion time of the TSC2013-Q1 device
depends on several functions. The conversion clock speed plays an important role in the time required for a
conversion to complete. However, proper sampling of the signal requires a certain number of internal clock
cycles. Moreover, additional times (such as the panel voltage-stabilization time), can add significantly to the time
it takes to perform a conversion. Conversion time can vary depending on the mode of use of TSC2013-Q1
device. This data sheet makes use of internal and conversion clock cycles throughout as the units used to
describe the amount of time that many functions take. Take these times into account when considering the total
system design.
7.3.3.5 Touch Detect
The PINTDAV pin can be programmed to generate an interrupt to the host. Figure 22 shows an example for a
typical screen-touch situation. While in the power-down mode, the Y– driver is on and connects to GND. The
internal pen-touch signal depends on whether or not the X+ input is low. A touch on the panel pulls the X+ input
to ground through the touch screen and sets the internal pen-touch output to low because of the detection on the
current path through the panel to ground, which initiates an interrupt to the processor. During the measurement
cycles for X and Y-position, the device disconnects the X+ input, which eliminates any leakage current from the
pullup resistor flowing through the touch screen, thus causing no errors.
Analog VDD
Plane
PINTDAV
SNSVDD
(1)
R(IRQ)
50 k
Y+
Connected
when a touch
is applied to
the screen
X+
Pen
Touch
SNSVDD
Level
Shifter
Control
Logic
Data Available from ADC
High when
the X+ or Y+
driver is on.
Sense
Y±
DGND
ON
High when the X+ or Y+
driver is on or when any
sensor connection or short
circuit tests are activated.
SNSGND
R(SENSE) Vias go to the system analog ground plane.
AGND
(1)
Untrimmed resistor; see the typical value in the table.
Figure 22. Example of a Pen-Touch Induced Interrupt via the PINTDAV Pin
20
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Feature Description (continued)
In modes where the TSC2013-Q1 device must detect whether or not a touch remains on the screen (for
example, when doing a pen-touch-initiated X, Y, and Z conversion), the TSC2013-Q1 device must reset the
drivers to connect the R(IRQ) resistor again. Because of the high value of this pullup resistor, any capacitance on
the touch screen inputs causes a long delay time, and may prevent the detection from occurring correctly. To
prevent this possible delay, the TSC2013-Q1 device has a circuit that allows prechargingd any screen
capacitance, so that the pullup resistor must not be the only source for the charging current. The setting for the
time allowed for this precharge, as well as the time needed to sense if the screen touch remains, is in the
configuration register.
This configuration underscores the need to use the minimum possible capacitor values on the touch-screen
inputs. Capacitors can be used to reduce noise, but capacitors with too large a value increase the required
precharge and sense times, as well as the panel voltage-stabilization time.
7.3.3.6 Preprocessing
The TSC2013-Q1 device offers an array of powerful preprocessing operations that reduce unnecessary traffic on
the bus and reduce the host processor loading. This reduction is especially critical for the serial interface
because of the slow bus speed and the high CPU bandwidth required for I2C communication.
All data-acquisition tasks are looking for specific data that meet certain criteria. Many of these tasks fall into a
predefined range, while other tasks may be looking for a value in a noisy environment. If the host processor is to
retrieve all these data for processing, the limited bus bandwidth quickly saturates, along with the host processor
processing capability. In any case, reserving the host processor for more critical tasks rather than routine work is
always necessary.
The preprocessing unit consists of two main functions which result in the combined MAV (median and averagingvalue) filter: the median value filter (MVF) and the averaging-value filter (AVF).
7.3.3.6.1 Preprocessing—Median Value Filter and Averaging Value Filter
The first preprocessing function, a combined MAV filter, can operate independently as a median value filter
(MVF), an averaging value filter (AVF), and a combined filter (MAV filter).
If the acquired signal source is noisy because of the digital switching circuit, evaluating the data without noise
may be necessary. In this case, the median value filter (MVF) operation helps to discard noise. The first action is
sorting the array of N converted results. The return value is either the middle (median value) of an array of M
converted results, or the average value of a window size of W of converted results:
N
= the total number of converted results used by the MAV filter
M
= the median value filter size programmed
W
= the averaging window size programmed
If M is equal to 1, then N is equal to W. A special case is W equal to 1, which indicates a bypassed MAV filter.
Otherwise, if W is greater than 1, averaging is the only function performed on these converted results. In either
case, the return value is the averaged value of window size W of converted results.
If M is greater than 1 and W is equal to 1, then N is equal to M, meaning the only operating filter is the median
value filter. The return value is the middle position converted result from the array of M converted results.
If M is greater than 1 and W is greater than 1, then N is equal to M. In this case, W is less than M. The return
value is the averaged value of middle portion W of converted results out of the array of M converted results.
Because the value of W is an odd number in this case, the calculation of the averaging value counts the middleposition converted result twice (averaging a total of W + 1 converted results).
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
21
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Feature Description (continued)
Table 1. Median Value Filter-Size Selection
M1
M0
MEDIAN VALUE FILTER
M=
POSSIBLE AVERAGING WINDOW SIZE
W=
0
0
1
1, 4, 8, 16
0
1
3
1
1
0
7
1, 3
1
1
15
1, 3, 7
Table 2. Averaging Value Filter-Size Selection
AVERAGING VALUE FILTER SIZE SELECTION
W=
W1
W0
M = 1 (Averaging Only)
M>1
0
0
1
1
0
1
4
3
1
0
8
7
1
1
16
Reserved
The device uses the default MVF setting (median value filter with averaging bypassed) for any invalid MAV filter
configuration. For example, if M1, M0, W1, and W0 equals 1, 0, 1, and 0 (respectively), the MAV filter will
perform as if it were configured for 1, 0, 0, 0, median filter only with filter size of 7, and no averaging. The only
exception is when M is greater than 1 and when W1 and W0 equal 1. Avoid using this reserved setting.
Table 3. Combined MAV Filter Setting
M
W
INTERPRETATION
N=
OUTPUT
=1
=1
Bypass both MAF and AVF
W
The converted result
=1
>1
Bypass MVF only
W
Average of W converted results
>1
=1
Bypass AVF only
M
Median of M converted results
M
Average of middle W of M converted results with the median
counted twice
>1
>1
M>W
The MAV filter is available for all analog inputs including the touch-screen inputs and the AUX measurement.
N measurements input
into temporary array
N Acquired
Data
N
M=1
N
W
Averaging output
from window W
M > 1 and W = 1
N
M
Median value
from array M
M > 1 and W > 1
N
M
Averaging output
from window W
Sort by
descending order
W
Figure 23. MAV Filter Operation
22
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.4 Device Functional Modes
7.4.1 Conversion Controlled by TSC2013-Q1 and Initiated by TSC2013-Q1 (TSMode 1)
In TSMode 1, before a pen-touch detection is possible, the TSC2013-Q1 device must be programmed with the
PSM bit set to 1 and one of two scan modes:
1. X-triplet, Y-triplet, Z-scan (converter function select bits C[3:0] = control byte 1 D[6:3] = 0000)
2. IX-IY scan (converter function select bits C[3:0] = control byte 1 D[6:3] = 0001).
See Table 7 for more information on the converter function-select bits.
On touching the touch panel, the internal pen-touch signal activates, lowering the PINTDAV output if
programmed as PENIRQ. The TSC2013-Q1 device then executes the preprogrammed scan function without a
host intervention.
7.4.1.1 IX-IY Scan
The TSC2013-Q1 device starts up the internal clock. The device then turns on the Y-drivers, and after a
programmed panel voltage-stabilization time, the device powers up the ADC and converts the IY coordinate.
With preprocessing selected, several conversions can occur. When data preprocessing is complete, a temporary
register stores the IY coordinate result.
If the screen touch remains at this time, the device enables the X-drivers and the process repeats but measures
the IX coordinate instead, storing the result in a temporary register.
Figure 24 shows a flowchart for this process. The time required to go through this process depends on the
selected resolution, internal conversion clock rate, panel voltage-stabilization time, precharge and sense times,
and the selection status of preprocessing. Use Equation 3 to calculate the time required to achieve a complete X
and Y coordinate (sample set) reading.
t(COORDINATE)
W(OH1)
¦(OSC)
§
§
ª
º ª 1 º ª W(PPRO) º ·
W d(OH1) ·
¦(OSC)
2 u ¨ t(PVS) t(PRE) t(SNS)
tc(OH) » u «
¸ 2 u ¨ N u «B 2 u
»«
»¸
¨
¨
¸
¦(OSC) ¹¸
¦(ADC)
©
¬«
¼» ¬« ¦(OSC) ¼» ¬« ¦(OSC) ¼» ¹
©
where
•
•
•
•
•
•
•
•
•
•
•
•
t(COORDINATE) = time to complete IX and IY coordinate reading
N = number of measurements for MAV filter input, as given in Table 3 as N
(For no MAV: M1 = M0 = W1 = W0 = 0)
t(PVS) = panel voltage stabilization time, as listed in Table 10
t(PRE) = precharge time, as listed in Table 10
t(SNS) = sense time, as listed in Table 10
B = number of bits of resolution
ƒ(OSC) = TSC onboard OSC clock frequency. See the Electrical Characteristics section for supply frequency
(SNSVDD)
ƒ(ADC) = ADC clock frequency, as listed in Table 10
t(OH1) = overhead time number 1 = 2.5 internal clock cycles
td(OH1) = total overhead time for t(PVS), t(PRE), and t(SNS) = 10 internal clock cycles
tc(OH) = total overhead time for A-to-D conversion = 3 internal clock cycles
t(PPRO) = preprocessor preprocessing time as listed in Table 4
(3)
Table 4. Preprocessing Delay
t(PPRO) =
M=
W=
FOR B = 12 BIT
1
1, 4, 8, 16
2
FOR B = 10 BIT
2
3, 7
1
28
24
7
3
31
27
15
1
31
29
15
3
34
32
15
7
38
36
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
23
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Programmed for
Self-Control
(PSM = 1)
IX-IY Scan Mode
(Control Byte1
D[6:3] = 0001)
TSC
Not Addressed
Reading
IX-Data
Register
Reading
IY-Data
Register
t(COORDINATE)
Sample, Conversion, and
Preprocessing for
IY Coordinate
Detecting Touch
PINTDAV Programmed:
Detecting
Touch
Touch is Detected
Sample, Conversion, and
Preprocessing for
IX Coordinate
Detecting
Touch
Sample, Conversion, and
Preprocessing for
IY Coordinate
Detecting
Touch
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
As DAV,
CFR2, D[15:14] = 11 or 01
Touch is Detected
As PENIRQ and DAV,
CFR2, D[15:14] = 00
Figure 24. Example of an IX and IY Touch-Screen Scan Using TSMode 1
7.4.1.2 X-Triplet, Y-Triplet, Z-Scan
The TSC2013-Q1 device starts up the internal clock. The device then turns on the Y-drivers, and after a
programmed panel voltage-stabilization time, powers up the ADC and converts the Y-triplet. With preprocessing
selected, several conversions can occur. When data preprocessing is complete, temporary registers store the Ytriplet results.
If the screen touch remains at this time, the device enables the X-drivers and the process repeats but measures
the X-triplet instead, storing the result in temporary registers.
The process continues in the same way, but measures the Z1 and Z2 values instead, storing the results in
temporary registers. When the complete sample set of data (X1, X2, IX, Y1, Y2, IY, Z1, and Z2) are available,
the device loads the data in the X1, X2, IX, Y1, Y2, IY, Z1, and Z2 registers. Figure 25 shows this process. This
process time depends on the previously described settings. Use Equation 4 to calculate the time for a complete
X1, X2, IX, Y1, Y2, IY, Z1, and Z2 coordinate reading.
W(OH2)
t(COORDINATE)
¦(OSC)
§
§
ª
º ª 1 º ª W(PPRO) º ·
W d(OH1) ·
¦(OSC)
3 u ¨ t(PVS) t(PRE) t(SNS)
tc(OH) » u «
¸ 8 u ¨ N u «B 2 u
»«
»¸
¨
¸
¨
¸
¦(OSC) ¹
¦(ADC)
©
¬«
¼» ¬« ¦(OSC) ¼» ¬« ¦(OSC) ¼» ¹
©
where
•
t(OH2) = overhead time number 2 = 3.5 internal clock cycles
Programmed for
Self-Control
(PSM = 1)
TSC
Not Addressed
(4)
Reading
X1, X2, IX, Y1, Y2, IY, Z1, Z2
Register
X1, X2, IX, Y1, Y2, IY, Z1, Z2
Scan Mode
(Control Byte1
D[6:3] = 0000)
t(COORDINATE)
Detecting
Touch
Sample, Conversion,
Sample, Conversion,
Detecting
Detecting
and Preprocessing for
and Preprocessing for
Touch
Touch
Y-Triplet
X-Triplet
PINTDAV Programmed:
Touch is Detected
Touch is Detected
Sample, Conversion,
Sample, Conversion,
Detecting
and Preprocessing for
and Preprocessing for
Touch
Z1 Coordinate and Z2 Coordinate
Y-Triplet
Detecting
Touch
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
As DAV,
CFR2, D[15:14] = 11 or 01
As PENIRQ and DAV,
CFR2, D[15:14] = 00
Touch is Detected
Figure 25. Example of an X-Triplet and Y-Triplet Coordinate Touch-Screen Scan Using TSMode 1
24
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.4.2 Conversion Controlled by TSC2013-Q1 and Initiated by Host (TSMode 2)
In TSMode 2, the TSC2013-Q1 device detects when a touch of the touch panel occurs and causes the internal
pen-touch signal to activate, which lowers the PINTDAV output if programmed as PENIRQ. The host recognizes
the interrupt request and then writes to the ADC control register to select one of the following two Touch-Screen
Scan functions:
1. X-triplet, Y-triplet, Z-scan (converter function select bits C[3:0] = control byte 1 D[6:3] = 0000); or
2. IX-IY scan (converter function select bits C[3:0] = control byte 1 D[6:3] = 0001).
See Table 7 for more information on the converter function-select bits.
The conversion process then proceeds as shown in Figure 26. See the IX-IY Scan and X-Triplet, Y-Triplet, ZScan sections for additional details.
The main difference between this mode and the previous mode is that the host, not the TSC2013-Q1 device,
decides when the touch-screen scan begins.
Use Equation 3 to calculate the time required to convert both IX and IY under host control (not including the time
required to send the command over the I2C bus):
Programmed
for
HostControlled
Mode
(PSM = 0)
TSC
Not
Programmed
Addressed
for
TSC
Not Addressed
IX-IY
Scan Mode
Reading
IX-Data
Register
Reading
IY-Data
Register
TSC
Not Addressed
t(COORDINATE)
Detecting
Touch
PINTDAV Programmed:
Waiting for Host to
Write Into
Control Byte 1 D[6:3]
Sample, Conversion,
and Preprocessing for
IY Coordinate
Detecting Sample, Conversion, Detecting Sample, Conversion, Detecting
and Preprocessing for
and Preprocessing for
Touch
Touch
Touch
IX Coordinate
IY Coordinate
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
Touch is Detected
As DAV,
CFR2, D[15:14] = 11 or 01
Touch is Still Here
As PENIRQ and DAV,
CFR2, D[15:14] = 00
Figure 26. Example of an IX and IY Touch-Screen Scan Using TSMode 2
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
25
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.4.3 Conversion Controlled by Host (TSMode 3)
In TSMode 3, the TSC2013-Q1 device detects a touch of the touch panel and causes the internal pen-touch
signal to be active, which lowers the PINTDAV output if programmed as PENIRQ. The host recognizes the
interrupt request. Instead of starting a sequence in the TSC2013-Q1 device, which then reads each coordinate in
turn, the host must now control all aspects of the conversion. Generally, on receiving the interrupt request, the
host turns on the X drivers.
NOTE
With the drivers turned off, the device detects this condition and turns the driver on before
the scan starts. This situation is why the event of turn on drivers is shown as optional in
Figure 27 and Figure 29.
After waiting for the settling time, the host then addresses the TSC2013-Q1 device again, this time requesting an
X-coordinate conversion.
The process then repeats for the Y and Z coordinates. Figure 27 and Figure 29 show this process. Figure 27
shows two consecutive scans on IX and IY. Figure 29 shows a single Z scan.
Use Equation 5 to calculate the time required to convert any single X-triplet or Y-triplet under host control (not
including the time required to send the command over the I2C bus):
§ª
º ª 1 º ª W(PPRO) º ·
W(OH1) §
W d(OH2) ·
¦(OSC)
t(COORDINATE)
¨ t(PRE) t(SNS)
tc(OH) » u «
¸ 3N u ¨ «B 2 u
»«
»¸
¨«
¸
¦(OSC) ©¨
¦(OSC) ¹¸
¦(ADC)
¼» ¬« ¦(OSC) ¼» ¬« ¦(OSC) ¼» ¹
©¬
where
•
td(OH2) = total overhead time for t(PRE) and t(SNS) = 6 internal clock cycles
Programmed
for HostControlled
Mode
(PSM = 0)
TSC
Not
Addressed
Programmed for:
Turn On
X+ and
X-Triplet
XMode
(1)
Drivers
Programmed for:
TSC
Not
Addressed
Reading
X1, X2,
IX
Register
Turn On
Y+ and Y-Triplet
YMode
(1)
Drivers
t(COORDINATE)
Detecting
Touch
Waiting for Host to Write Into
Control Byte 1 D[6:3]
PINTDAV Programmed:
Touch is Detected
Sample, Conversion,
and Preprocessing
for X-Triplet
(5)
TSC
Not
Addressed
TSC
Not
Reading Addressed
Y-Data
Register
t(COORDINATE)
Detecting Waiting for Host to Write Into
Control Byte 1 D[6:3]
Touch
Sample, Conversion,
and Preprocessing
for Y-Triplet
Detecting
Touch
Waiting for Host to
Write Into Control
Byte 1 D[6:3]
Touch is Detected
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
As DAV,
CFR2, D[15:14] = 11 or 01
As PENIRQ and DAV,
CFR2, D[15:14] = 00
(1)
Optional. If not turned on, it will be turned on by the scan mode, when detected.
Figure 27. Example of X-Triplet and Y-Triplet Touch-Screen Scan
(Without Panel Stabilization Time) Using TSMode 3
26
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Use Equation 6 to calculate the time required to convert any single X-triplet or Y-triplet under host control (not
including the time required to send the command over the I2C bus):
t(COORDINATE)
W(OH1)
¦(OSC)
Programmed for
Host-Controlled
Mode
(PSM = 0)
§ª
§
º ª 1 º ª W(PPRO) º ·
W d(OH2) ·
¦(OSC)
¨ t(PVS) t(PRE) t(SNS)
tc(OH) » u «
¸ 3N u ¨ «B 2 u
»«
»¸
¨
¨«
¸
¦(OSC) ¹¸
¦
¦
¦
»
«
»
«
»
(ADC)
(OSC)
(OSC)
©
¬
¼
¬
¼
¬
¼¹
©
(6)
TSC
Programmed
Not Addressed
for
X-Triplet
Scan Mode
TSC
Not Addressed
TSC
Not Addressed
Reading
X1 , X2 , IX
Data
Register
t(COORDINATE)
Detecting
Touch
Waiting for Host to Write
Into Control Byte 1 D[6:3]
Sample, Conversion, and
Preprocessing for X-Triplet
Detecting
Touch
Waiting for Host to Write
Into Control Byte 1 D[6:3]
PINTDAV Programmed:
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
As DAV,
CFR2, D[15:14] = 11 or 01
Touch is Still Here
As PENIRQ and DAV,
CFR2, D[15:14] = 00
Figure 28. Example of a Single X-Triplet Touch-Screen Scan
(With Panel Stabilization Time) Using TSMode 3
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
27
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Use Equation 7 to calculate the time required to convert any Z1 and Z2 coordinate under host control (not
including the time required to send the command over the I2C bus):
W(OH2)
t(COORDINATE)
¦(OSC)
§ª
§
º ª 1 º ª W(PPRO) º ·
W d(OH2) ·
¦(OSC)
¨ t(PRE) t(SNS)
t c(OH) » u «
¸ N u ¨ «B 2 u
»«
»¸
¨
¨
¸
¦(OSC) ¹¸
¦(ADC)
©
¼» ¬« ¦(OSC) ¼» ¬« ¦(OSC) ¼» ¹
© ¬«
(7)
Programmed for:
TSC
Not
Addressed
Programmed
for
Host-Controlled
Mode
(PSM = 0)
Turn On
Y+
and
XDrivers(1)
Z
Scan
Mode
TSC
Not Addressed
Reading
Z1-Data
Register
TSC
Not Addressed
Reading
Z2-Data
Register
t(COORDINATE)
Detecting
Touch
Waiting for Host to Write
Into Control Byte 1 D[6:3]
PINTDAV Programmed:
Sample, Conversion, Sample, Conversion,
and Preprocessing
and Preprocessing
for Z2 Coordinate
for Z1 Coordinate
Detecting
Touch
Touch is Detected
Waiting for Host to Write
Into Control Byte 1 D[6:3]
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
As DAV,
CFR2, D[15:14] = 11 or 01
As PENIRQ and DAV,
CFR2D[15:14] = 00
(1)
Optional. If not turned on, it will be turned on by the scan mode, when detected.
Figure 29. Example of Z1 and Z2 Coordinate Touch-Screen Scan
(Without Panel Stabilization Time) Using TSMode 3
If the drivers do not turn on prior to programming the touch-screen scan mode, include the panel stabilization
time. In this case, use Equation 8 to calculate the time required to convert any single X or Y under host control
(not including the time required to send the command over the I2C bus):
§ª
º ª 1 º ª W(PPRO) º ·
W(OH2) §
Wd(OH2) ·
¦(OSC)
¨ t(PVS) t(PRE) t(SNS)
tc(OH) » u «
t(COORDINATE)
¸ N u ¨ «B 2 u
»«
»¸
¨
¸
¨«
¸
¦(OSC) ©
¦(OSC) ¹
¦(ADC)
¼» ¬« ¦(OSC) ¼» ¬« ¦(OSC) ¼» ¹
©¬
(8)
Programmed for
Host-Controlled
Mode
(PSM = 0)
TSC
Programmed
Not Addressed
for
Z1-Z2
Scan Mode
TSC
Not Addressed
Reading
Z1-Data
Register
Reading
Z2-Data
Register
TSC
Not Addressed
t(COORDINATE)
Detecting
Touch
Waiting for Host to Write
Into Control Byte 1 D[6:3]
PINTDAV Programmed:
Sample, Conversion, and
Preprocessing for Z1, Z2 Coordinates
Detecting
Touch
Waiting for Host to Write
Into Control Byte 1 D[6:3]
Touch is Detected
As PENIRQ,
CFR2, D[15:14] = 10
As DAV,
CFR2, D[15:14] = 11 or 01
Touch is Still Here
As PENIRQ and DAV,
CFR2D[15:14] = 00
Figure 30. Example of a Z1 and Z2 Coordinate Touch-Screen Scan
(With Panel Stabilization Time) Using TSMode 3
28
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.5 Programming
7.5.1 I2C Interface
The TSC2013-Q1 device supports the I2C serial bus and data transmission protocol in all three defined modes:
standard, fast, and high-speed. A device that sends data onto the bus has the definition of a transmitter, and a
device receiving data that of a receiver. The device that controls the message is a master. Devices controlled by
the master are slaves. A master device that generates the serial clock (SCL), controls bus access, and generates
the START and STOP conditions must control the bus The TSC2013-Q1 device operates as a slave on the I2C
bus. Connections to the bus are through the open-drain I/O lines, SDA and SCL.
The following bus protocol has been defined (see Figure 31):
• A device can initiate data transfer only when the bus is not busy.
• During data transfer, the data line must remain stable whenever the clock line is high. Changes in the data
line while the clock line is high are interpreted as control signals.
Accordingly, definitions for the following bus conditions follow:
Bus Not Busy Both data and clock lines remain high.
Start Data Transfer A change in the state of the data line, from high to low, while the clock is high, defines a
start condition.
Stop Data Transfer A change in the state of the data line, from low to high, while the clock line is high, defines
the stop condition.
Data Valid
The state of the data line represents valid data, when, after a start condition, the data line is stable
for the duration of the high period of the clock signal. One clock pulse occurs per bit of data.
Each data transfer begins with a start condition and terminates with a stop condition. The
number of data bytes transferred between start and stop conditions, which the master device
determines, is not limited. The information transfers byte-wise, and the receiver
acknowledges each byte with a ninth bit.
The I2C bus specifications define a standard mode (100-kHz clock rate), a fast mode (400kHz clock rate), and a high-speed mode (3.4-MHz clock rate). The TSC2013-Q1 device
works in all three modes.
Acknowledge Each receiving device, when addressed, must generate an acknowledge after the reception of
each byte. The master device must generate an extra clock pulse for association with this
acknowledge bit.
A device that acknowledges must pull down the SDA line during the acknowledge clock
pulse in such a way that the SDA line is stable low during the high period of the
acknowledge clock pulse. Of course, the timing must take into account setup and hold times.
A master must signal an end-of-data to the slave by not generating an acknowledge bit on
the last byte that clocks out of the slave. In this case, the slave must leave the data line high
to enable the master to generate the stop condition.
Figure 31 shows the data-transfer process on the I2C bus. Depending on the state of the R/W bit, two types of
data transfer are possible:
1. Data transfer from a master transmitter to a slave receiver.
The first byte transmitted by the master is the slave address. A number of data bytes occurs next. The slave
returns an acknowledge bit after the slave address and each received byte.
2. Data transfer from a slave transmitter to a master receiver.
The master transmits the first byte, the slave address. The slave then returns an acknowledge bit. Next, the
slave transmits a number of data bytes to the master. The master returns an acknowledge bit after all
received bytes other than the last byte. At the end of the last received byte, the master returns a notacknowledge.
The master device generates all of the serial clock pulses and the start and stop conditions. A transfer ends with
a stop condition or a repeated start condition. Because a repeated start condition is also the beginning of the
next serial transfer, the bus is not released.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
29
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Programming (continued)
The TSC2013-Q1 device can operate in the following two modes:
1. Slave receiver mode
Reception of serial data and clock is through SDA and SCL. After the reception of each byte, the receiver
transmits an acknowledge bit. Start and stop conditions designate the beginning and end of a serial transfer.
Hardware performs address recognition after reception of the slave address and direction bit.
2. Slave transmitter mode
Reception and handling of the first byte (the slave address) is the same as in the slave receiver mode.
However, in this mode the direction bit indicates a reversal of the transfer direction. Serial data transmission
on SDA by the TSC2013-Q1 device occurs during input of the serial clock on SCL. Start and stop conditions
designate the beginning and end of a serial transfer.
7.5.1.1 I2C Fast or Standard Mode (F-S Mode)
In I2C fast or standard (F-S) mode, serial data transfer must meet the timing shown in the timing requirement
tables in the Specifications section.
In the serial transfer format of F-S mode, the master signals the beginning of a transmission to a slave with a
start condition (S), which is a high-to-low transition on the SDA input while SCL is high. When the master has
finished communicating with the slave, the master issues a stop condition (P), which is a low-to-high transition on
SDA while SCL is high, as shown in Figure 31. The bus is free for another transmission after the occurrence of a
stop. Figure 31 shows the complete F-S mode transfer on the I2C, two-wire serial interface. Transmission of the
address byte, control byte, and data byte is between the start and stop conditions. The SDA state can only
change while SCL is low, except for the start and stop conditions. Data transmission is in 8-bit words. Nine clock
cycles are necessary to transfer the data into or out of the device (8-bit word plus acknowledge bit).
P
or
Sr
S
SDA
MSB
Slave Address
R/W
Direction Bit
Acknowledgement
Signal from Receiver
Acknowledgement
Signal from Receiver
SCL
1
2
6
7
8
9
1
2
3-8
8
ACK
9
ACK
Repeated If More Bytes Are Transferred
= Resistor Pull Up
S = START Condition
Sr = Repeated START Condition
P = STOP Condition
Figure 31. Complete Fast or Standard-Mode Transfer
30
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Programming (continued)
7.5.1.2 I2C High-Speed Mode (Hs Mode)
Serial data transfer format in high-speed (Hs) mode meets the fast or standard (F-S) mode I2C bus specification.
Hs mode can only commence after the following conditions (all of which are in F-S mode) exist:
1. Start condition (S)
2. 8-bit master code (0000 1xxx)
3. Not-acknowledge bit (N)
Figure 32 shows this sequence in more detail. Hs-mode master codes are reserved 8-bit codes used only for
triggering Hs mode. Do not use these codes for slave addressing or any other purpose. The master code
indicates to other devices that an Hs-mode transfer is about to begin and the connected devices must meet the
Hs mode specification. Because no device can acknowledge the master code, a not-acknowledge bit (N) follows
the master code.
After the not-acknowledge bit (N) and SCL achieve a high level, the master switches to Hs-mode and enables (at
time t(H); shown in Figure 32) the current-source pullup circuit for SCL. Because other devices can delay the
serial transfer before t(H) by stretching the LOW period of SCL, the master enables the current-source pullup
circuit when all devices have released SCL and SCL has reached a high level, thus speeding up the last part of
the rise time of the SCL.
The master then sends a repeated start condition (Sr) followed by a 7-bit slave address with an R/W bit address,
and receives an acknowledge bit (A) from the selected slave. After a repeated start (Sr) condition and after each
acknowledge bit (A) or not-acknowledge bit (N), the master disables the current-source pullup circuit. This
disabling enables other devices to delay the serial transfer by stretching the low period of SCL. The master reenables the current-source pullup circuit again when all devices have released, and SCL reaches a high level,
which speeds up the last part of the SCL signal rise time.
Data transfer continues in Hs mode after the next repeated start (Sr), and only switches back to F-S mode after a
stop condition (P). To reduce the overhead of the master code, the master can link to a number of Hs mode
transfers, separated by repeated start conditions (Sr).
8-Bit Master Code 00001xxx
S
N
tH
SDA
SCL
1
2 to 5
6
7
8
9
Fast or Standard Mode
R/W
7-Bit Slave Address
Sr
A
n x (8-Bit DATA
+
A/N)
Sr P
SDA
SCL
1
2 to 5
6
7
8
9
1
2 to 5
6
7
8
9
If P then
Fast or Standard Mode
High-Speed Mode
tH
= Current-Source Pull Up
= Resistor Pull Up
If Sr (dashed lines
)
then High-Speed Mode
A = Acknowledge (SDA LOW)
N = Not Acknowledge (SDA HIGH)
S = START Condition
P = STOP Condition
Sr = Repeated START Condition
tFS
Figure 32. Complete High-Speed Mode Transfer
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
31
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Programming (continued)
7.5.2 Digital Interface
7.5.2.1 Address Byte
The TSC2013-Q1 device has a 7-bit slave address word. The factory presets the first five bits (MSBs) of the
slave address to comply with the I2C standard for ADCs; the setting is always 1 0010. The logic state of the
address input pins (AD1 through AD0) determines the two LSBs of the device address to activate
communication. Therefore, one bus can accommodate a maximum of four devices with the same preset code at
one time.
The device only reads the AD1 through AD0 address inputs during a power-up of the device, and the pin
connections should be to a digital supply (I/OVDD) or digital ground (DGND). The TSC2013-Q1 latches the slave
address on the falling edge of SCL after reception of the R/W bit by the slave.
The last bit of the address byte (R/W) defines the operation to be performed. Setting the bit to 1 selects a read
operation. Setting the bit to 0 selects a write operation. Following the start condition, the TSC2013-Q1 device
monitors the SDA bus, checking the transmitted device-type identifier. On receiving the 1 0010 code, the
appropriate device select bits, and the R/W bit, the slave device outputs an acknowledge signal on the SDA line.
Table 5. I2C Slave Address Byte
MSB
D7
D6
D5
D4
D3
D2
D1
LSB
D0
1
0
0
1
0
AD1
AD0
R/W
R/W (D0)
1: I2C master read from TSC (I2C read addressing).
0: I2C master write to TSC (I2C write addressing).
I2C Write-Addressing Byte
S/Sr
1
0
0
1
0
AD1 AD0
0
START or
Repeated START
A
From Master to Slave
A = Acknowledge (SDA LOW)
S = START Condition
ACK
From Slave to Master
Sr = Repeated START Condition
I2C Read-Addressing Byte
S/Sr
1
0
0
1
0
START or
Repeated START
AD1 AD0
1
A
ACK
Figure 33. I2C Bus Addressing (Slave-Address Byte Format)
32
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.5.3 Control Byte
Table 6. Control Byte Format: Start a Conversion and Mode Setting, D7 = 1
MSB
D7
1
(Control Byte 1)
D6
D5
D4
D3
D2
D1
LSB
D0
C3
C2
C1
C0
RM
SWRST
STS
Control Byte ID (D7)
1: Control Byte 1 (start conversion and channel select and conversion-related
configuration).
0: Control Byte 0 (read/write data registers and non-conversion-related controls).
C[3:0] (D6:D3)
Converter function select bits
These bits select the input for conversion, and the converter function to be executed.
Table 7 lists the possible converter functions.
RM (D2)
Resolution select
If RM = 1, the conversion-result resolution is 12-bit; otherwise, the resolution is 10-bit.
This bit is the same RM bit shown in CFR0.
0: 10-bit
1: 12-bit
SWRST (D1)
Software reset. This bit is self-clearing.
1: Reset all register values to default
STS (D0)
Stop bit for all converter functions. This bit is self-clearing.
On writing a 1 to this register, this bit aborts the converter function currently running in
the TSC2013-Q1. An automatic write of 0 to this register occurs when the abort has
completed. Setting this bit to 1 can only stop converter functions; it does not reset any
data, status, or configuration registers. This bit is the same STS bit shown in CFR0, but
reading can only be through the CFR0 register.
Write 0: Normal operation
Write 1: Stop converter functions and power down
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
33
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Table 7. Converter Function Select
C3
C2
C1
C0
0
0
0
0
Touch-Screen Scan function: X triplet, Y triplet, Z1, and Z2 coordinates converted and the results returned to X1, X2,
IX, Y1, Y2, IY, Z1, and Z2 data registers. Scan continues until either lifting of the pen or sending of a stop bit.
0
0
0
1
Touch-Screen Scan function: IX and IY coordinates converted and the results returned to IX and IY data registers.
Scan continues until either lifting of the pen or sending of a stop bit.
0
0
1
0
Touch screen function: X triplet converted and the results returned to X1, X2, IX data register.
0
0
1
1
Touch screen function: Y triplet converted and the results returned to Y1, Y2, IY data register.
0
1
0
0
Touch screen function: Z1 and Z2 coordinates converted and the results returned to Z1 and Z2 data registers.
0
1
0
1
Auxiliary input converted and the results returned to the AUX data register.
0
1
1
0
Touch screen function: IX converted and result returned to IX data register.
0
1
1
1
Touch screen function: IY converted and result returned to IY data register.
1
0
0
0
Auxiliary input conversion occurs continuously and the results returned to the AUX data register.
1
0
0
1
RESERVED
1
0
1
0
RESERVED
1
0
1
1
RESERVED (1)
1
1
0
0
RESERVED
1
1
0
1
X+, X– drivers activated
1
1
1
0
Y+, Y– drivers activated
1
1
1
1
Y+, X– drivers activated
(1)
FUNCTION
Any condition caused by this command can be cleared by setting the STS bit to 1.
Table 8. Control Byte Format: Start a Conversion and Mode Setting D7 = 0
MSB
D7
0
(Control Byte 0)
D6
D5
D4
D3
D2
D1
LSB
D0
A3
A2
A1
A0
Reserved
(Write 0)
PND0
R/W
Control byte ID (D7)
1: Control byte
configuration
1—start
conversion,
channel
select,
and
conversion-related
0: Control byte 0—read/write data registers and non-conversion-related controls
A[3:0] (D6:D3)
Register address bits as detailed in Table 9
RESERVED (D2)
Set a 0 in this bit for normal operation
PND0 (D1)
Power-not-down control
1: ADC biasing circuitry is always on between conversions but shuts down after the
converter function stops
0: ADC biasing circuitry shuts down either between conversions or after the converter
function stops. Example power savings for the following condition is approximately 5%:
AUX conversion, continuous mode, median filter = 15, averaging filter = 7, ƒ(ADC) = 2
MHz.
R/W (D0)
TSC internal-register data-flow control
1: Set the starting address of the TSC internal registers for a register read (see
Figure 34)
0: Write to TSC internal registers
34
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.5.3.1 Touch-Screen Scan Function for XYZ or XY
These scan functions (C3–C0 = 0000 or 0001) can collaborate with the PSM bit that defines the control mode of
converter functions. With the PSM bit set to 1, TI recommends issuing these scan-function select commands
before detection of a pen touch in order to allow the TSC2013-Q1 device to initiate and control the scan
processes immediately after detection of the screen touched. Without issuing these functions before detection of
a pen touch, the TSC2013-Q1 waits for the host to write these functions before starting a scan process. If PSM
stays as 1 after a TSC-initiated scan function is complete, the host is not required to write these function-select
bits again for each of the following pen touches after the detected touch. In the host-controlled converter function
mode (PSM = 0), the host must send these functions select bits repeatedly for each scan function after a
detected pen touch.
NOTE
The update of the data registers may occur while a host reading is in progress. Using the
sequential read cycle (see Figure 35) prevents the TSC from updating registers while a
host reading is in progress. To ensure a correct reading of the XYZ or XY coordinates, use
the sequential read cycle to read the coordinates after the scan.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
35
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Table 9. Internal Register Map
REGISTER ADDRESS
A3
A2
A1
A0
REGISTER CONTENT
READ/WRITE
0
0
0
0
X1 measurement result
R
0
0
0
1
X2 measurement result
R
0
0
1
0
Y1 measurement result
R
0
0
1
1
Y2 measurement result
R
0
1
0
0
IX measurement result
R
0
1
0
1
IY measurement result
R
0
1
1
0
Z1 measurement result
R
0
1
1
1
Z2 measurement result
R
1
0
0
0
Status
R
1
0
0
1
AUX measurement result
R
1
0
1
0
RESERVED
1
0
1
1
RESERVED
1
1
0
0
CFR0
R/W
1
1
0
1
CFR1
R/W
1
1
1
0
CFR2
R/W
1
1
1
1
Converter function select status
R
R/W is the register read and write control. A 1 indicates that the value of the internal register address bits A3–A0
is stored internally as the starting address for a register read (see Figure 34). The content of the addressed
register is sent to SDA by using I2C read addressing (see Figure 35 and Figure 36). A0 indicates that the data
following control byte 0 on SDA are written into the internal register addressed by bits A3–A0 (see Figure 34).
7.5.4 Start a Write Cycle
A write cycle begins when the master issues the slave address to the TSC2013-Q1 device. The slave address
consists of seven address bits and a write bit (R/W = 0; see Table 6).On receipt of the eighth bit, if the address
matches the AD1 through AD0 address input pin setting, the TSC2013-Q1 device issues an acknowledge bit by
pulling SDA low for one additional clock cycle (ACK = 0); see Figure 33.
When the master receives the acknowledge bit from the TSC2013-Q1 device, the master writes the input control
byte to the slave (see Table 6). After the control byte is received by the slave, the slave issues another
acknowledge bit by pulling SDA low for one clock cycle (ACK = 0). The master then ends the write cycle by
issuing a STOP or repeated START condition; see Figure 34.
36
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Write Cycle
START
I C Slave Address
2
I C WriteAddressing Byte
0 A
8
Control Byte 1
ACK 1 C3 C2 C1 C0 RM
A P
STS
S
1
SWRST
7
2
STOP(1)
Converter Function Select
START
I C Slave Address
I2C WriteAddressing Byte
0 A
8
8
Control Byte 0
ACK 0 A3 A2 A1 A0
Rsvd
S
1
Data Byte 1/2
(HIGH Byte)
A
PND0
7
2
8
A
Data Byte 2/2
(LOW Byte)
A P
STOP(1)
0
TSC Internal Register Address for Write Data
START
I C Slave Address
2
I C WriteAddressing Byte
0 A
8
Control Byte 0
ACK 0 A3 A2 A1 A0
Rsvd
S
1
A P
PND0
7
2
STOP(1)
1
TSC Internal Register Starting Address mh(2)
(M + N × 3) × 8
7
S
I2C Slave Address
1
0 A
2
START
I C WriteAddressing Byte
From Master to Slave
From Slave to Master
A
A
A P
Mixed M (Control Byte 1 or Control Byte 0 with Read Bit)
Plus N (Control Byte 0 with Data Bytes), Separated by TSC ACKs
STOP(1)
A = Acknowledge (SDA LOW)
N = Not Acknowledge (SDA HIGH)
S = START Condition
P = STOP Condition
Sr = Repeated START Condition
(1)
In order to start the next sequence, a stop condition must be followed by a start condition. If no stop is used, then a
repeated start (Sr) must be used. Also note that if a stop condition is issued in high-speed mode, the mode reverts to
the previous mode which is either fast or standard mode.
(2)
mh is a hexadecimal number.
Figure 34. Write Cycle
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
37
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.5.5 Register Access
Data access begins with the master issuing a START (or repeated START) condition followed by the 7-bit
address and a read bit (R/W = 1; see Table 6). On receipt of the eighth bit has been received and an address
match, the slave issues an acknowledge by pulling SDA low for one clock cycle (ACK = 0). The first byte of serial
data then follows. After the slave has sent the first byte, it then releases the SDA line for the master to issue an
acknowledge (ACK = 0). The slave issues the second byte of serial data on receiving the acknowledgment from
the master (D7–D0), followed by a not-acknowledge bit (ACK = 1) from the master to indicate receipt of the last
data byte has been received. The master then issues a STOP condition (P) or repeated START (Sr), which ends
the read cycle, as shown in Figure 35 and Figure 36. If the master issues a not-acknowledge (ACK = 1) after
receipt of the first data byte, the master must then issue a stop condition (P) to reset the registers. If the master
is not ready to receive the second data byte, it should issue the acknowledge (ACK = 0), or the master should
stretch the clock. On restart of the clock, the master can receive the second byte of data.
Read Cycle: Sequential, from Register Address mh(2) to (m + n)h(3)
7
S
START
I2C Slave Address
1
8
8
1
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
A
I2C Read-Addressing Byte
A
A
Register (Address = mh) Content
8
8
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
A
A
Register (Address = (m + 1)h) Content
8
8
NACK
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
A
Register (Address = (m + n)h) Content
From Master to Slave
From Slave to Master
P
STOP(1)
A = Acknowledge (SDA LOW)
N = Not Acknowledge (SDA HIGH)
S = START Condition
P = STOP Condition
Sr = Repeated START Condition
(1)
In order to start the next sequence, a Stop condition must be followed by a start condition. If no stop is used, then a
repeated start must be used. Also note that if a stop condition is issued in high-speed mode, the mode reverts to the
previous mode which is either fast or standard mode.
(2)
mh is a hexadecimal number.
(3)
If (m+n)h is greater than Fh, then (m + n)h is modulo 16.
Figure 35. Sequential Read Cycle
38
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Read Cycle: Repeated, Register Address mh(2)
7
S
START
2
I C Slave Address
START
8
8
NACK
1
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
A
2
I C Read-Addressing Byte
7
S
1
2
I C Slave Address
1
8
8
NACK
1
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
A
START
I C Slave Address
1
A
A
P
STOP(1)
Register (Address = mh) Content
7
S
P
STOP(1)
Register (Address = mh) Content
I2C Read-Addressing Byte
2
A
8
8
NACK
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
I2C Read-Addressing Byte
A
P
STOP(1)
Register (Address = mh) Content
Or...
7
Sr
2
I C Slave Address
1
8
8
NACK
1
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
A
Repeated I2C Read-Addressing Byte
START
7
Sr
2
I C Slave Address
Register (Address = mh) Content
1
8
8
NACK
1
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
A
Repeated I2C Read-Addressing Byte
START
Sr
I C Slave Address
1
Repeated I2C Read-Addressing Byte
START
From Master to Slave
From Slave to Master
A
Register (Address = mh) Content
7
2
A
A
8
8
NACK
Data Byte 1/2
(HIGH Byte)
Data Byte 2/2
(LOW Byte)
N
A
Register (Address = mh) Content
P
STOP(1)
A = Acknowledge (SDA LOW)
N = Not Acknowledge (SDA HIGH)
S = START Condition
P = STOP Condition
Sr = Repeated START Condition
(1)
In order to start the next sequence, a Stop condition must be followed by a start condition. If no stop is used, then a
repeated start must be used. Also note that if a stop condition is issued in high-speed mode, the mode reverts to the
previous mode which is either fast or standard mode.
(2)
mh is a hexadecimal number.
Figure 36. Repeated Read Cycle
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
39
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.5.6 Communication Protocol
All control of the TSC2013-Q1 is through registers. Reading and writing to these registers are accomplished by
the use of Control Byte 0, which includes a 4-bit address plus one read-write TSC register-control bit. The data
registers defined in Table 9 are all 16-bit, right-adjusted.
NOTE
Except for some configuration registers and the status register that are full 16-bit registers,
the rest of the value registers are 12-bit (or 10-bit) data preceded by four (or six) zeros.
See the Configuration and Status Registers section for the register field descriptions.
7.5.7 Register Reset
The TSC2013-Q1 device can be reset in one of three ways. First, at power-on, a power-good signal generates a
prolonged reset pulse internally to all registers.
Second, an external pin, RESET, is available to perform a system reset or allow other peripherals (such as a
display) to reset the device if the pulse meets the timing requirement (at least 10 μs in duration). Any RESET
pulse less than 5 μs is rejected. To accommodate the timing drift between devices because of process variation,
a RESET pulse duration between 5 μs and 10 μs falls into the gray area that is unrecognized, giving an
undetermined result; avoid this situation. See Figure 37 for details. A good reset pulse must be low for at least 10
μs. An internal spike filter is available to reject spikes up to 20 ns wide.
t(WL_RESET) < 5 µs
tr
tr
t(WL_RESET) ³ 10 µs
RESET
State
Normal Operation
Resetting
Initial Condition
NOTE: See the timing requirement tables in the Specifications section for more information.
Figure 37. External Reset Timing
Third, a software reset is activated by writing a 1 to CB1.1 (bit 1 of control byte 1). Note that this reset is not selfclearing, so the user must write a 0 to remove the software reset.
A reset clears all registers and loads default values. A power-on reset and external (hardware) reset take
precedence over a software reset. If the user does not clear a software reset, either a power-on reset or an
external (hardware) reset clears it.
40
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.6 Register Maps
The TSC2013-Q1 device has several 16-bit registers that allow control of the device, as well as providing a location to store results from the TSC2013-Q1
device until read out by the host microprocessor. shows the memory map.
Register Content and Reset Values (1)
D15
D14
D13
D12
D11
D10
D9
D8
D7
D6
D5
D4
D3
D2
D1
D0
RESET
VALUE
(HEX)
0
X1
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
1
X2
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
2
Y1
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
3
Y2
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
4
IX
T (2)
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
5
IY
T (2)
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
6
Z1
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
7
Z2
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
8
Status
DAVX
DAVY
DAVZ
1
DAVZ
2
DAVA
UX
0
0
0
RESE
T
0
0
0
0
PDST
0
0
0004
A3-A0
(HEX)
(1)
(2)
REGISTER
NAME
9
AUX
0
0
0
0
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
0000
A
RSVD
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0000
B
RSVD
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0000
C
CFR0
PSM
STS
RM
CL1
CL0
PV2
PV1
PV0
PR2
PR1
PR0
SN2
SN1
SN0
DTW
LSM
4000
D
CFR1
0
0
0
0
0
0
0
0
0
0
0
0
0
BTD2
BTD1
BTD0
0000
MAVE
Y TRIPLET
MAVE
Z
MAVE
AUX
0
0000
R3
R2
R1
R0
0000
E
CFR2
PINTS1
PINTS0
M1
M0
W1
W0
0
0
0
0
0
MAVE
X TRIPLET
F
CFN
CFN15
CFN14
CFN13
0
0
0
0
CFN8
CFN7
R6
R5
R4
For all combination bits, do not use the pattern marked as RSVD (reserved). The default pattern is read back after reset.
Use of the D15 bit only occurs during a single IX or single IY conversion command.
T = 0: No touch detected during conversion
T = 1: Touch detected during conversion
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
41
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.6.1 Configuration and Status Registers
7.6.1.1 Configuration Register 0
7.6.1.1.1 Configuration Register 0 (address = 0) [reset = 4000h for read; 0000h for write]
Figure 38. Configuration Register 0
D15
PSM
R/W-Reset
D14
STS
R/W-
D13
RM
R/W-
D12
D7
D6
PR[2:0]
R/W-
D5
D4
D11
D10
D9
PV[2:0]
R/W-
D8
D3
SN[2:0]
R/W-
D2
D1
DTW
R/W-
D0
LSM
R/W-
CL[1:0]
R/W-
Table 10. Configuration Register 0 Field Descriptions
Bit
Field
Type
Reset
Description
D15
PSM
R/W
0
Pen status or control mode. This bit is the MSB.
Reading this bit allows the host to determine if a touch of the screen has
occurred. Writing to this bit selects the mode used to control the flow of
converter functions that are either initiated and/or controlled by host or under
control of the TSC2013-Q1 responding to a pen touch. When reading, the PSM
bit indicates if the pen is down or not. When writing to this register, this bit
determines if the TSC2013-Q1 or the host controls the converter functions. The
default state is the host-controlled converter function mode (0). The other state
(1) is the TSC-initiated scan function mode that must only collaborate with
C3–C0 = 0000 or 0001 in order to allow the TSC2013-Q1 to initiate and control
the scan function for XYZ or XY when a on detection of a pen touch.
0 (R): No screen touch detected
1 (R): Screen touch detected
0 (W): Converter functions initiated and/or controlled by host
1 (W): Converter functions initiated and controlled by the TSC2013Q1
D14
STS
R/W
1 for R
0 for W
ADC status
When reading, this bit indicates if the converter is busy or not busy. Continuous
scans or conversions can be stopped by writing a 1 to this bit, immediately
aborting the running converter function (even if the pen is still down) and
causing the ADC to power down. The default state for write is 0 (normal
operation), and the default state for read is 1 (converter is not busy). Note that
the same bit can be written through Control Byte 1 (bit 0). This bit is selfclearing.
0 (R): Converter is busy
1 (R): Converter is not busy
0 (W): Normal operation
1 (W): Stop converter function and power down
D13
RM
R/W
0
Resolution control
This bit specifies the ADC resolution. See for a description of these bits. This bit
is the same whether reading or writing, and defaults to 0. Note that one cn write
the same bit through Control Byte 1.
0: 10-bit resolution. Default after power up and reset
1: 12-bit resolution
42
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Table 10. Configuration Register 0 Field Descriptions (continued)
Bit
D12-D11
Field
Type
Reset
Description
CL[1:0]
R/W
0
Conversion-clock control
These two bits specify CL bits that specify the clock rate that the ADC uses to
perform conversion.
CL1 = 0, CL0 = 0: ƒ(ADC) = ƒ(OSC) / 1, referred to as the 4-MHz ADC clock
rate, 10-bit resolution only
CL1 = 0, CL0 = 1: ƒ(ADC) = ƒ(OSC) / 2, referred to as the 2-MHz ADC clock
rate
CL1 = 1, CL0 = 0: ƒ(ADC) = ƒ(OSC) / 4, referred to as the 1-MHz ADC clock
rate
CL1 = 1, CL0 = 1: ƒ(ADC) = ƒ(OSC) / 4, referred to as the 1-MHz ADC clock
rate
D10-D8
PV[2:0]
R/W
0
Panel-voltage stabilization-time control
These bits specify a delay time from the moment of touch-screen drivers
enabling to the time of voltage sampling and the start of a conversion. These
bits allow the user to adjust the appropriate settling time for the touch panel and
external capacitances. See for settings of these bits. The default state is 000,
indicating a 0-μs stabilization time (t(PVS)). These bits are the same whether
reading or writing.
PV2 = 0, PV1 = 0, PV0 = 0: 0 μs
PV2 = 0, PV1 = 0, PV0 = 1: 100 μs
PV2 = 0, PV1 = 1, PV0 = 0: 500 μs
PV2 = 0, PV1 = 1, PV0 = 1: 1 ms
PV2 = 1, PV1 = 0, PV0 = 0: 5 ms
PV2 = 1, PV1 = 0, PV0 = 1: 10 ms
PV2 = 1, PV1 = 1, PV0 = 0: 50 ms
PV2 = 1, PV1 = 1, PV0 = 1: 100 ms
D7-D5
PR[2:0]
R/W
0
Precharge time selection
These bits set the amount of time allowed for precharging any pin capacitance
on the touch screen prior to sensing whether a pen touch is in progress. The
following lists the precharge time (t(PRE))
PR2 = 0, PR1 = 0, PR0 = 0: 20 μs
PR2 = 0, PR1 = 0, PR0 = 1: 84 μs
PR2 = 0, PR1 = 1, PR0 = 0: 276 μs
PR2 = 0, PR1 = 1, PR0 = 1: 340 μs
PR2 = 1, PR1 = 0, PR0 = 0: 1.044 ms
PR2 = 1, PR1 = 0, PR0 = 1: 1.108 ms
PR2 = 1, PR1 = 1, PR0 = 0: 1.3 ms
PR2 = 1, PR1 = 1, PR0 = 1: 1.364 ms
D4-D2
SN[2:0]
R/W
0
Sense-time selection
These bits set the amount of time the TSC2013-Q1 device waits after converting
a coordinate to sense whether a screen touched is in progress.
SNS2 = 0, SNS1 = 0, SNS0 = 0: 32 μs
SNS2 = 0, SNS1 = 0, SNS0 = 1: 96 μs
SNS2 = 0, SNS1 = 1, SNS0 = 0: 544 μs
SNS2 = 0, SNS1 = 1, SNS0 = 1: 608 μs
SNS2 = 1, SNS1 = 0, SNS0 = 0: 2.08 ms
SNS2 = 1, SNS1 = 0, SNS0 = 1: 2.144 ms
SNS2 = 1, SNS1 = 1, SNS0 = 0: 2.592 ms
SNS2 = 1, SNS1 = 1, SNS0 = 1: 2.656 ms
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
43
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Table 10. Configuration Register 0 Field Descriptions (continued)
Bit
Field
Type
Reset
Description
D1
DTW
R/W
0
Detection of pen touch in wait (patent pending)
Writing a 1 to this bit enables pen-touch detection in the background while
waiting for the host to issue the converter function in host-initiated and controlled modes. This background detection allows the TSC2013-Q1 to pull
PINTDAV high to indicate no pen touch detected while waiting for the host to
issue the converter function. If the host polls a high state at PINTDAV before the
transmission of the convert function, the host can abort the issuance of the
convert function and stay in the polling PINTDAV mode until the detection of the
next pen touch.
D0
LSM
R/W
0
Longer sampling mode. This bit is the LSB.
With this bit set to 1, an extra 500 ns of sampling time is added to the normal
sampling cycles of each conversion. This additional time is represented as
approximately two internal oscillator clock cycles.
44
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.6.1.2 Configuration Register 1 (address = Dh) [reset = 0000h]
Configuration register 1 (CFR1) defines the connection test-bit modes configuration and batch-delay selection.
Figure 39. Configuration Register 1
D15
D14
D13
D12
D11
D10
D9
D8
D3
D2
D1
BTD[2:0]
R/W-0
D0
RESERVED
W-0
D7
D6
D5
RESERVED
W-0
D4
Table 11. Configuration Register 1 Field Descriptions
Bit
Field
Type
Reset
D15-D3
RESERVED
W
0
D2-D0
BTD[2:0]
R/W
0
Description
Batch time-delay mode
These are the selection bits that specify the delay before the triggering of a
sample or conversion scan cycle. When it is set, Batch time-delay mode uses a
set of timers to trigger a sequence of sample-and-conversion events
automatically. The mode works for both TSC-initiated scans (XYZ or XY) and
host-initiated scans (XYZ or XY).
Configure a TSC-initiated scan (XYZ or XY) by setting the PSM bit in CFR0 to 1
and C[3:0] in control byte 1 to 0000 or 0001. In the case of a TSC-initiated scan
(XYZ or XY), the sequence begins with the TSC responding to a pen touch.
After the first processed sample set completes during the batch delay, the scan
enters a wait mode until the end of the batch delay. If detection of a pen touch
persists at that moment, the scan continues to process the next sample set,
along with a resumption of the batch delay. The selected batch delay during the
time of the detected pen touch regulates the throughput of the processed
sample sets (shown in as sample sets per second, or SSPS). One can
configure a TSC-initiated scan (XYZ or XY) by setting the PSM bit in CFR0 to 1
and C[3:0] in control byte 1 to 0000 or 0001. Note that the throughput of the
processed sample set also depends on the settings of stabilization, precharge,
and sense times, and the total number of samples to be processed per
coordinates. If the accrual time of these factors exceeds the batch delay time,
the accrual time dominates. Batch delay time starts when the pen touch initiates
the scan function that converts coordinates.
One can configure a host-initiated scan (XYZ or XY) by setting the PSM bit in
CFR0 to 0 and C[3:0] in control byte 1 to 0000 or 0001. For the host-initiated
scan (XYZ or XY), the host must set TSC internal register C[3:0] in control byte
1 to 0000 or 0001 initially after a pen-touch detection; see . After engagement of
the scan (XYZ or XY), the selected batch-delay timer regulates the throughput
of the processed sample sets, as long as the initial detected touch is
uninterrupted.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
45
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Table 11. Configuration Register 1 Field Descriptions (continued)
Bit
Field
Type
Reset
Description
Throughput for TSC-initiated or host-initiated scan, XYZ OR XY:
BTD2 = 0, BTD1 = 0, BTD0 = 0, td = 0: Normal operation throughput
depends on settings
BTD2 = 0, BTD1 = 0, BTD0 = 1, td = 1: 1000 SSPS
BTD2 = 0, BTD1 = 1, BTD0 = 0, td = 2: 500 SSPS
BTD2 = 0, BTD1 = 1, BTD0 = 1, td = 4: 250 SSPS
BTD2 = 1, BTD1 = 0, BTD0 = 0, td = 10: 100 SSPS
BTD2 = 1, BTD1 = 0, BTD0 = 1, td = 20: 50 SSPS
BTD2 = 1, BTD1 = 1, BTD0 = 0, td = 40: 25 SSPS
BTD2 = 1, BTD1 = 1, BTD0 = 1, td = 100: 10 SSPS
For example, if stabilization time, precharge time, and sense time are selected
as 100 μs, 84 μs, and 96 μs, respectively, and the batch delay time is 2 ms,
then the scan function enters wait mode after the first processed sample set
until the 2 ms of batch-delay time expires. When the scan function starts to
process the second sample set (if a touch is still present on the screen), the
batch delay restarts at 2 ms (in this example). This procedure remains regulated
by 2 ms until the pen touch is undetected or a stop bit or any reset form stops
the scan function.
46
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.6.1.3 Configuration Register 2 (address = Eh) [reset = 0000h]
Configuration register 2 (CFR2) defines the preprocessor configuration.
Figure 40. Configuration Register 2
D15
PINTS1
R/W-0
D14
PINTS0
R/W-0
D13
D7
D6
RESERVED
D5
D12
M[1:0]
R/W-00
D10
D9
W[1:0]
R/W-00
D4
MAVE
X TRIPLET
R/W-0000
W-0
D11
D3
MAVE
Y TRIPLET
R/W-0000
D8
RESERVED
W-0
D2
MAVE
Z
R/W-0000
D1
MAVE
AUX
R/W-0000
D0
RESERVED
W-0
Table 12. Configuration Register 2 Field Descriptions
Bit
Field
Type
Reset
Description
D15
PINTS1
R/W
0
This bit controls the output format of the PINTDAV pin. With this
bit set to 0, the output format is the AND-form of internal signals
of PENIRQ and DAV). With this bit set to 1, PINTDAV outputs
PENIRQ only.
PINTDAV PIN OUTPUT =
0: AND combination of PENIRQ (active-low) and DAV (activehigh).
0: Data available, DAV (active-low).
1: Interrupt, PENIRQ (active-low) generated by pen-touch.
1: Data available, DAV (active-low).
D14
PINTS0
R/W
0
This bit selects the output on the PINTDAV pin. With this bit set
to 0, the output format of PINTDAV depends on the selection
made on the PINTS1 bit. With this bit set to 1, PINTDAV outputs
the internal signal of DAV.
PINTDAV PIN OUTPUT =
0: AND combination of PENIRQ (active-low) and DAV (activehigh).
1: Data available, DAV (active-low).
0: Interrupt, PENIRQ (active-low) generated by pen-touch.
1: Data available, DAV (active-low).
D13-D12
M[1:0]
R/W
00
Preprocessing MAV filter control
Note that when the MAV filter is processing data, the STS bit
and the corresponding DAV bits in the status register indicate
that the converter is busy until all conversions necessary for the
preprocessing are complete. The default state for these bits is
0000, which bypasses the preprocessor. These bits are the
same whether reading or writing.
D11-D10
W[1:0]
R/W
00
Preprocessing MAV filter control
Note that when the MAV filter is processing data, the STS bit
and the corresponding DAV bits in the status register indicate
that the converter is busy until all conversions necessary for the
preprocessing are complete. The default state for these bits is
0000, which bypasses the preprocessor. These bits are the
same whether reading or writing.
D9-D5
RESERVED
W
0
D4-D1
MAVE
R/W
0000
MAV-filter function-enable bit
When any bit is set to 1, the MAV filter setup is applied to the
corresponding measurement.
D0
RESERVED
Copyright © 2014, Texas Instruments Incorporated
W
0
Submit Documentation Feedback
47
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.6.1.4 Converter-Function Select Register (address = Fh) [reset = 0000h]
The converter-function select (CFN) register reflects the converter function select status.
Figure 41. Converter-Function Select Register
D15
D14
CFN[15:13]
R-0
D13
D6
D5
D7
D12
D11
D10
D9
D8
CFN[8:0]
R-0
D2
D1
D0
RESERVED
R-0
D4
D3
CFN[8:0]
R-0
Table 13. Converter-Function Select Register Field Descriptions
Bit
D15-D13
Field
Type
Reset
Description
CFN[15:13]
R
0
Touch-screen driver status
These bits represent the current status of the turned-on touchscreen drivers. The device sets CFN13 to 1 with both X+ and X–
drivers turned on, CFN14 to 1 with both Y+ and Y– drivers
turned on, and CFN15 to 1 with Y+ and X– drivers turned on.
Otherwise, the device sets these bits to 0. The device resets
these bits to 000b whenever the converter function is complete,
stopped by the STS bit, or reset (by a hardware reset from the
RESET pin or a software reset from SWRST bit in control byte
1).
D12-D9
RESERVED
R
0
D8-D0
CFN[8:0]
R
0
Converter function-select status.
These bits represent the converter function currently running,
which is set in bits C3–C0 of control byte 1. When the CFNx bit
shows 1, where x is the decimal value of converter functionselect bits C3–C0, it is an indication that the converter function
set in bits C3–C0 is running. For example, when CFN2 shows 1,
it indicates the converter function set in bits C3-C0 (0010) is
running. Reset of the CFNx bits to 0000h occurs whenever the
converter function is complete, stopped by STS bit, or reset (by
the hardware reset from the RESET pin or the software reset
from SWRST bit in Control Byte 1). However, if the TSC sets the
PSM bit in the CFR0 register to 1 to initiate the scan-function
mode, reset of the CFN0 or CFN1 does not occur when the
corresponding converter function is complete, because there is
no pen touch. This event allows the TSC2013-Q1 to initiate the
scan process (corresponding to CFN0 or CFN1 set to 1)
immediately on detection of the next pen touch.
48
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
7.6.1.5 Status Register (address = 8h) [reset = 0004h]
The Status Register provides information about the TSC2013-Q1 status.
Figure 42. Status Register
D15
DAV
Due
X TRIPLET
D14
DAV
Due
Y TRIPLET
D7
RESET
Flag
R-0
D6
D13
DAV
Due
Z1
R-0
D12
DAV
Due
Z2
D11
DAV
Due
AUX
D10
D9
D8
RESERVED
R-0
D5
RESERVED
D4
D3
D2
PDST
R-0
R-1
D1
D0
RESERVED
R-0
Table 14. Status Register Field Descriptions
Bit
Field
Type
Reset
Description
D15-D11
DAV
R
0
Data available bits
These five bits mirror the operation of the internal signals of
DAV. On storing any processed data in data registers, the DAV
bit (D15 to D11) corresponding to the data type is set to 1. The
bIt stays at 1 until the registers updated to the host has read out
the processed data. If the user submits a single IX or single IY
conversion command, bit D15 or D14 (respectively) shows data
availability. In this case, only data register IX or IY receives an
update.
0: No new processed data are available.
1: Processed data are available. This bit remains at 1 until
the host has read out all updated registers.
D10-D8
D7
RESERVED
R
0
RESET
R
0
Interpretation of the RESET flag bits:
0: Device was reset since the last status poll (hardware or
software reset).
1: Device reset has not occurred since the last status poll.
D6-D3
D2
RESERVED
R
0
PDST
R
1
Power-down status
This bit reflects the setting of the PND0 bit in Control Byte 0.
When this bit shows 0, it indicates ADC bias circuitry power is
still on after each conversion and before the next sampling;
otherwise, it indicates ADC bias circuitry power is down after
each conversion and before the next sampling. However, power
is down between conversion sets. Because this status bit is in
synchrony with the internal clock, it does not reflect the setting of
the PND0 bit until detection of a pen touch is detected or
initiation of a converter function.
D1-D0
RESERVED
Copyright © 2014, Texas Instruments Incorporated
R
0
Submit Documentation Feedback
49
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
7.6.2 Data Registers
The data registers of the TSC2013-Q1 hold data results from conversions. All of these registers default to 0000h
on reset.
7.6.2.1 X1, X2, IX, Y1, Y2, IY, Z1, Z2, and AUX registers (offset = see ) [reset = see ]
The results of all ADC conversions are placed in the appropriate data registers, as described in Table 9. The
data format of the result word (R) of these registers is right-justified, as shown in .
Figure 43. X1, X2, IX, Y1, Y2, IY, Z1, Z2, and AUX Registers
D15
D14
D13
D12
D11
R11 (1)
R-0
D10
R10 (1)
R-0
D9
R9
R-0
D8
R8
R-0
D5
R5
R-0
D4
R4
R-0
D3
R3
R-0
D2
R2
R-0
D1
R1
R-0
D0
R0
R-0
RESERVED
R-0
D7
R7
R-0
(1)
D6
R6
R-0
R11 and R10 are 0 in 10-bit mode.
Table 15. X1, X2, IX, Y1, Y2, IY, Z1, Z2, and AUX Register Field Descriptions
Field
Type
Reset
Description
D15-D12
Bit
RESERVED
R
0
Use of the D15 bit only occurs during a single IX or single IY
conversion command (see ).
T = 0: No touch detected during conversion
T = 1: Touch detected during conversion
D11-D0
R[11:0]
R
0
12-bit data
50
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
8 Application and Implementation
8.1 Application Information
8.1.1 Auxiliary Measurement
The TSC2013-Q1 device can measure the voltage from the auxiliary input (AUX). Applications for the AUX can
include external temperature sensing, ambient light monitoring for controlling backlighting, or sensing the current
drawn from batteries. Two converter functions can be used for the measurement of the AUX:
1. Non-continuous AUX measurement as shown in Figure 44 (converter function select bits C[3:0] = control
byte 1 D[6:3] = 0101)
2. Continuous AUX measurement as shown in Figure 45 (converter function select bits C[3:0] = control byte 1
D[6:3] = 1000)
See Table 7 for more information on the converter function select bits.
Use Equation 9 to calculate the time required to make a non-continuous auxiliary measurement.
W(OH3)
t(COORDINATE)
¦(OSC)
§
· § 1 · § W(PPRO) ·
¦(OSC)
N u ¨ B 2 u
tc(OH) ¸ u ¨
¸¨
¸
¨
¸ ¨ ¦(OSC) ¸ ¨ ¦(OSC) ¸
¦(ADC)
©
¹ ©
¹ ©
¹
where
•
t(OH3) = overhead time number 3 = 3.5 internal clock cycles.
TSC
Not Addressed
Programmed for
Non-Continuous
AUX Measurement
(9)
TSC
Not Addressed
TSC
Not Addressed
Reading
AUX-Data
Register
t(COORDINATE)
No Touch
Detected
Host Write to
Control Byte 1 D[6:3]
Sample, Conversion, and
Averaging for AUX Measurement
No Touch
Detected
Waiting for Host to
Read AUX Data
As DAV
Figure 44. Non-Touch Screen, Non-Continuous AUX Measurement
Use Equation 9 to calculate the time required to make a continuous auxiliary measurement.
TSC
Not Addressed
No Touch
Detected
Programmed for
Continuous
AUX Measurement
Host to Write to
Control Byte 1 D[6:3]
TSC
Not
TSC
Reading Not Addressed Reading Addressed
AUX-Data
AUX-Data
Register
Register
TSC
Not Addressed
t(COORDINATE)
t(COORDINATE)
t(COORDINATE)
Sample, Conversion,
and Averaging for
AUX Measurement
Sample, Conversion,
and Averaging for
AUX Measurement
Sample, Conversion,
and Averaging for
AUX Measurement
As DAV
Figure 45. Non-Touch Screen, Continuous AUX Measurement
8.1.2 Single IX or Single IY Measurement
Figure 46 shows the sequence for a single IX or single IY measurement.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
51
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
Application Information (continued)
TSC
Not Addressed
TSC
Not Addressed
Single IX or
Single IY Measurement
TSC
Not Addressed
Reading
IX or IY Data
Register
t(COORDINATE)
No Touch
Detected
Sample, Conversion, and
Averaging for IX or IY Measurement
Host Write to
Control Byte 1 D[6:3]
Waiting for Host to
Read IX or IY Data
No Touch
Detected
As DAV
Figure 46. Touch Screen, Single IX or IY Measurement
8.2 Typical Application
1.6 VDC
1 µF
0.1 µF
1.6 VDC
AGND
Y+
I/OVDD
SNSVDD/VREF
X+
1.2 kΩ
PINTDAV
X–
GPIO
SDA
SDA
AD1
AD0
AUX
AGND
Y–
SNSGND
SCL
Touch
Screen
Host
Processor
GPIO
RESET
TSC2013-Q1
1.2 kΩ
SCL
(PINTDAV is optional;
software implementation
polling of the Status register is
possible)
AGND
R(SENSE)
47 Ω
Figure 47. Typical Application Diagram
8.2.1 Design Requirements
The system-level requirements for this design include:
• Normal 4-wire resistive touch screen with low activation force (from center area down to 0.1 to 0.3 N) to
enable smooth dual-touch operation.
• The R(SENSE) resistor value is the lowest panel resistance (X or Y layer) which is approximately 4.5. This
resistor value provides the best dynamic range for dual-touch separation.
• To achieve the best possible SNR, select the highest operating voltage of the TSC2013-Q1 device that is
compatible with the system.
8.2.2 Detailed Design Procedure
Resistive dual touch using TSC2013-Q1 device is based on the principle of measuring resistance changes
between X and Y panel. The resistive touch screen has two ITO layers which are located apart from each other.
When the user uses a single-finger touch, only a minor parallel connection occurs between these two layers.
52
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Typical Application (continued)
During a dual-finger touch when the finger touches are located on different areas of the screen, parallel
connection is much higher which results in a reduction in panel resistance. Because the TSC2013-Q1 device
measures both X and Y-layer panel resistance, the finger touch distance can be easily calculated from the
resistance change. This calculation is achieved by using one external resistor the is connected internally in series
with the measured X-Y panel.
Use the following methods to enable the dual-touch function of the TSC2013-Q1 device:
• Measure all four nodes and use those measurements to calculate center point of the finger touch.
• Use the measurements of the four nodes to correctly place the touch positions to the correct quadrants.
• Measure the two-layer panel resistance by using a single external resistor that is connected internally in
series with measured panel layer. A change in resistance is interpreted as a change in finger distance.
All calculations are performed by the host-side processor. The TSC2013-Q1 device provides only data.
The following sections describe the design procedure in detail.
8.2.2.1 Power-On-Reset and Reset Consideration
The TSC2013-Q1 device can be rest to the default working state in one of three ways. These resets are: poweron reset (see the Power-On Reset section), hardware reset (see the Hardware Reset section), and software
reset (see the Software Reset section).
The requirements for ensuring a proper TSC2013-Q1 power-on reset (POR) are very stringent and can be very
hard to meet in many applications. To workaround this issue, users should apply a proper hardware or software
reset, instead of or in addition to the POR.
8.2.2.1.1 Power-On Reset
Based on design principles and extensive tests with TSC2013-Q1 device, the power of the device must meet a
specific on-off timing and sequence to ensure the POR is implemented during each TSC2013-Q1 power on. This
specific timing and sequence also ensures that a lockup is prevented.
During the device power on, the POR brings the TSC2013-Q1 device into a known default working state by
initializing the internal state machine, data and control registers, and the condition of the output pins. Without the
POR, the TSC2013-Q1 device can power on in a random state and can cause the PINTDAV pin to respond
incorrectly.
The TSC2013-Q1 POR circuit was designed to not consume power during normal operation. The power-down
current is kept as low as possible (0.8-µA maximum power-down supply current).
This POR circuit in TSC2013-Q1 device requires specific power-up and power-down ramps and sequences.
Figure 48 shows and Table 16 lists the recommended power-off times, on-ramp, and off-ramp specifications.
t(SNSVDD_OFF_ramp)
t(SNSVDD_ON_ramp)
SNSVDD
0V
t(SNSVDD_OFF)
Figure 48. POR Sequence
Table 16. Requested POR Timings
TEMPERATURE RANGE
MINIMAL t(SNSVDD_OFF_ramp)
MINIMAL t(SNSVDD_ON_ramp)
MINIMAL t(SNSVDD_OFF) (1)
–40°C to –21°C
12 kV/s
12 kV/s
1.2 s
–20°C to 85°C
2 kV/s
12 kV/s
200 ms
(1)
t(SNSVDD_OFF) time begins when the SNSVDD pin voltage reaches and stays at 0 V.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
53
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
8.2.2.1.2 Requesting a Minimal t(SNSVDD_OFF) Time
The POR circuit of the TSC2013-Q1 device contains a capacitor that is charged when the device powers up
which generates an internal reset signal. This capacitor is discharged after the TSC2013-Q1 supply is switched
off. The TSC2013-Q1 device is designed for low-power operation, therefore the POR requires time to charge and
discharge the capacitor, especially under cold temperatures (less than –20°C). If the SNSVDD off time is not
sufficient, the device can lock up. Only a power recycle can resolve this lockup condition.
8.2.2.1.3 Requesting a Minimal t(SNSVDD_OFF_ramp) and t(SNSVDD_ON_ramp) Ramp
To ensure proper initialization of the TSC2013-Q1 device, the device must reach a certain voltage before the
internal POR signal is released. If the power supply on the ramp is too slow the device can power up in a random
state which can cause a lock up.
The capacitor inside the POR circuit must be discharged through the SNSVDD pin. To support a proper
discharge when the TSC2013-Q1 supply is switched off, TI recommends to provide a low resistance path on the
SNSVDD pin.
8.2.2.1.4 Hardware Reset
The hardware reset pin, RESET, is available to perform a system reset which resets the device if the pulse width
meets the timing requirement (at least 10-µs wide and the SNSVDD/VREF or I/OVDD pin is greater than or equal
to 1.6 V). Any reset pulse less than 5 µs is rejected. To accommodate the timing drift between devices because
of process variation, a reset pulse width between 5 µs and 10 µs is not recognized and the result is
undetermined. This situation should be avoided. A good reset pulse must be low for at least 10 µs
(SNSVDD/VREF or I/OVDD pin is greater than or equal to 1.6 V). An internal spike filter rejects spikes up to 20
ns wide. See Figure 37 for the hardware reset timing diagram.
8.2.2.1.5 Software Reset
During normal operation a software reset can be sent by the host processor to the device by setting the SWRST
bit (D1) to 1 in the control byte 1 (see Table 6).
8.2.2.2 Power Up Considerations
8.2.2.2.1 Power-Off Cycles During Normal Operation
The TSC2013-Q1 device is a low-power device and therefore switching the TSC2013-Q1 device off during
normal operation is not needed nor recommended.
Every power cycle (power on → power off → power on) must meet the requirements described in the Power-On
Reset section. If requirements cannot be met, TI recommends to issue a hardware reset after every power cycle.
8.2.2.2.2 Supply Glitches During Normal Operation
A TSC2013-Q1 SNSVDD or IOVDD power glitch during normal operation can cause a lockup condition.
Therefore ensure that the system is able to either recycle the power in the system following the requirements
described in the Power-On Reset section or issue a hardware reset as described in the Hardware Reset section.
54
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
8.2.2.2.3 TSC2013-Q1 Digital Pins
In many applications, users use the same power supply for both the TSC2013-Q1 analog and digital supplies.
The SNSVDD supply is connected with the I/OVDD supply. Under such cases, the logic high status on the
TSC2013-Q1 digital pins before power-up become a concern when performing a proper POR.
Table 17 lists the digital I/O pins of the TSC2013-Q1 device.
Table 17. TSC2013-Q1 Digital Pin List
TSC2013-Q1 PINS
DESCRIPTION
PINTDAV
Digital Output. Data available or the pen-detect interrupt (PENIRQ), depending on setting. Pin polarity
is active-low.
RESET
Digital input. External hardware reset input (active-low).
SCL
Open drain and collector. Serial clock
SDA
Open drain and collector. Serial data I/O
A0
Digital input. I2C bus TSC address input bit 0
A1
Digital input. I2C bus TSC address input bit 1
Every TSC2013-Q1 pin is well protected against ESD strikes. The TSC2013-Q1 RESET, A0, and A1 pins have
the same protection as the SDA and SCL pins. This protection allows the RESET, A0, and A1 pins to be pulled
high before the device powers on without activating an internal ESD diode and without causing a power up of the
TSC2013-Q1.
The output pin, PINTDAV, is a digital output pin. The host processor must define the PINTDAV pin as an input to
the host processor without any pullup-pulldown feature. In some cases the default of the host processor is an
output with an enabled pullup-pulldown feature but the host-processor firmware changes this definition at a later
point to an input. If the TSC2013-Q1 device is not powered up, a power up can also occur through the ESD cells
as shown in by the red line in Figure 49. This power up is considered a false power up. A false power up cannot
ensure a proper power supply to the device or a proper POR.
In case the TSC2013-Q1 device is powered up, both the device and drive processor drive different levels on the
same line resulting in high power consumption.
The TSC2013-Q1 PINTDAV pin should be connected to the correct pin on the host processor to avoid bus
conflicts and illegal powering up of the TSC2013-Q1 device.
I/OVDD
PINTDAV
Digital Output
TSC2013-Q1
GND
Figure 49. Internal ESD Protection Diodes at the TSC2013-Q1 PINTDAV Pin
8.2.2.2.4 Suggested Hardware Reset During Power-On
The suggested sequence during power up is the following:
• Keep RESET pin low
• Wait for the supplies to settle
• Wait for at least 10µs before releasing the RESET pin
Figure 50 shows the suggested waveform.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
55
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
SNSVDD
I/OVDD
> 10 µs
RESET
Figure 50. Suggested RESET Waveform During Power-On
8.2.2.3 Device Timing Setup and Use
The TSC2013-Q1 device is a register-based touch-screen controller (TSC). This section describes the setup and
use of the programable timings available in the TSC2013-Q1 device.
Figure 52 through Figure 56 in the Application Curves were generated to show the principal. The TSC2013-Q1 X
triplet contains X1, X2, and IX conversions. The TSC2013-Q1 Y triplet contains Y1, Y2, and IY conversions. The
TSC2013-Q1 Z measurement contains Z1 and Z2 conversions.
8.2.2.3.1 Touch-Panel Driving Power
On a resistive touch-screen system, the driving current of the touch panel, provided by the TSC device through
the analog interface, has the highest impact on the power consumption in the touch screen system. This touchpanel power consumption is decided by the resistance of the touch panel and the TSC power-supply (SNSVDD)
voltage. Figure 51 shows this relationship. The touch screen is driven by the TSC from the SNSVDD supply and
the resistance of the panel determines the peak drive current.
Figure 51 only shows the ideal TSC driving condition where the internal resistance of the TSC is ignored
because the resistance is small (5 to 6 Ω) compared to the resistance of the touch panel (100s to 1000s Ω).
Therefore the actual power consumption should be a little less than that shown in Figure 51.
A
•
•
•
user can reduce power consumption in three ways:
Using touch screens with higher resistance
Using a low-power supply, SNSVDD, to the TSC
Reducing the driver on-time or the on-off ratio of the driver
Touch panels with higher resistance are likely to cause more noise and longer settling time which limits the
options for users.
The TSC20013-Q1 device is designed with a power supply, SNSVDD, range of 1.6 V to 3.6 V.
Reducing the driver on-time involves setting various touch-screen timings and delays. lists the relevant
parameters concerning these timings and delays. The following sections describe the functions and effects of
these timings and delays. See the Register Maps section for the timing settings of the configuration registers.
8.2.2.3.2 ADC Clock Effects
A TSC2013-Q1 device contains a nominal 4-MHz internal clock that is used to drive the state machines inside
the device which performs the many functions. This clock is divided down to provide a clock to run the SAR ADC
(analog-to-digital converter). If the 4-MHz clock is used directly (divided by 1), the ADC is limited to a 10-bit
resolution, then using higher resolutions at this speed does not result in accurate conversions. The 12-bit
resolution requires that the conversion clock run at either 2 MHz (divided by 2) or 1 MHz (divided by 4). The
division ratio for the ADC clock is set in the configuration register 0 (CFR0), by setting the CL1 and CL0 bits (see
Table 6).
The ability to change the conversion clock rate allows the user to select the optimal value for the ADC resolution,
speed, and power dissipation. Higher clock frequency results in faster touch-data converting speed and shorter
touch-driver on-time which usually result in lower SNSVDD power consumption. Figure 52 and Figure 53 show
examples of the ADC clock effect on the analog interface traffic (X+, X–, Y+, and Y– lines). In these figures, a
TSC drives the touch panel to acquire the X, Y, Z1, and Z2 coordinates and three samples-per-coordinate.
56
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
Figure 52 shows an analog interface with the clock frequency set to 2 MHz. Figure 53 shows an analog interface
with the clock frequency set to 1-MHz. In Figure 52 and Figure 53, other than the ADC clock frequency
difference, all other settings are completely identical with the following values: PVS equal to 0 µs, PR equal to 20
µs, and SN equal to 32 µs (see the Panel Voltage Stabilization Time section for more information on these
timers).
The ADC clock frequency determines the length of the TSC acquisition time and TSC driver on-time. The faster
the ADC clock, the shorter the driver on-time. For example, sampling 3 Y data with an ADC clock value of 2 MHz
(see Figure 52) uses only about half of the time compared to sampling the data with an ADC clock value of 1
MHz (see Figure 53).
Use Equation 10 to calculate the analog power-supply current, I(SNSVDD).
I(SNSVDD)
§ V(SNSVDD) · § SSPS u S u B ·
f V(SNSVDD) ¨¨
¸
¸¸ u ¨¨
¸
5
¦(OSC)
©
¹ ©
¹
where
•
•
•
•
•
•
•
f(V(SNSVDD)) is a function of V(SNSVDD)
V(SNSVDD) is the SNSVDD voltage (in V)
R is the average resistance of the touch panel (in Ω)
SSPS is sample sets-per-second, which indicates how many sets of touch data is received by the host within a
second
S is the number of data in a set of samples
B is the TSC resolution, either 10 bit or 12 bit
ƒ(OSC) is ADC clock frequency, which can be 4, 2, or 1 MHz
(10)
Equation 10 includes two parts: the internal circuitry power consumption or f(V(SNSVDD)) and the current to drive
the external resistive-touch panel which is calculated using Equation 11.
I(TOUCHPANEL)
§ V(SNSVDD) · § SSPS u S u B ·
¸
¨¨
¸¸ u ¨¨
¸
5
¦(OSC)
©
¹ ©
¹
(11)
A concern for using the faster ADC clock is because of the settling time or transients of the analog interface. The
higher clock frequency can reduce the accuracy of the data in those cases where the TSC begins the data
acquisitions before the analog interface lines reach the stable voltages. Therefore, adding some delays on the
analog interface in order to wait for the interface to become stable before an ADC begins working might be
necessary. These delays can include the panel voltage-stabilization time, the precharge time of the pins, the
sense time (see the Panel Voltage Stabilization Time section), or a combination.
8.2.2.4 Panel Voltage Stabilization Time
The panel voltage-stabilization time, td(PVS), specifies a delay time from the moment the touch screen drivers are
enabled to the time the voltage is sampled and a conversion is started. These bits allow the user to adjust the
appropriate settling time for the touch panel based on the external capacitances at the analog interface lines.
Figure 54 shows examples where with td(PVS) is 0 µs (no PVS delay), 100 µs, and 500 µs. In the examples, the
TSC uses the sets of 4 × 3 = 12 data which are 3 X, 3 Y, 3 Z1, and 3 Z2. The TSC2013-Q1 device always
performs the Y coordinate first when it was set to X-Y or X-Y-Z scan mode. The sequence for receiving a set of
samples in Figure 54 is as follows:
1. The TSC adds driver power to Y+ (SNSVDD) and Y– (AGND), waits td(PVS) µs, and acquires 3 Y data
2. The TSC adds driver power to X+ (SNSVDD) and X– (AGND), waits td(PVS) µs, and acquires 3 X data
3. The TSC adds driver power to Y+ (SNSVDD) and X– (AGND), waits td(PVS) µs, and acquires 3 Z1 and 3 Z2
data
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
57
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
The PVS delay consumes power because a driver is on during the PVS delay. Use Equation 12 to calculate the
power.
§ V(SNSVDD) ·
P ¨¨
¸¸ u SSPS u t d(PVS) u 3
R
©
¹
where
•
3 indicates that the X, Y, and Z drivers are on
(12)
Based on Equation 10, use Equation 13 to calculate a complete expression of the analog power consumption for
X-Y-Z 3-dimension coordinates.
P
§ V(SNSVDD)
u SSPS u
f V(SNSVDD) ¨¨
R
©
ªS u B
º·
« F 3 u t d(PVS) » ¸¸
¬
¼¹
(13)
Use Equation 14 to calculate the power consumption for X-Y 2-dimension touch data.
P
§ V(SNSVDD)
u SSPS u
f V(SNSVDD) ¨¨
R
©
ªS u B
º·
« F 2 u t d(PVS) » ¸¸
¬
¼¹
where
•
2 indicates that the X and Y drivers are on
(14)
8.2.2.5 Precharge and Sense Time
Unlike the ADC clock frequency (bits CL1 to CL0) and panel voltage-stabilization time (bits PV2 to PV0), the
other two TSC timings in the CFR0 register (see Table 6) affect the bus shape and traffic speed but do not effect
power consumption of the analog interface.
As shown in Figure 54, some added time or delays occur between samples of two coordinates such as after
sampling Y and before the X driver turns on. This added time or delay is the precharge time (bits PR2 to PR0)
and sense time (bits SN2 to SN0).
The precharge time sets the amount of time allowed for precharging any pin capacitance on the touch screen
during TSC ADC conversions as shown in Figure 55.
The sense time sets the amount of delay for the TSC device to wait between two coordinates during TSC ADC
conversions as shown in Figure 56.
If a pressure remains on the touch panel, the TSC devices can automatically and continuously acquire touch
data. As many as several-thousand SSPS of touch data can be driven on, sampled, converted, and processed.
For a typical application, however, users usually need only 100 to 500 SSPS of touch data because of the control
and response limits of a human. To save power, users often do not want the system to acquire any unnecessary
data.
The SSPS of a TSC can be reduced in several ways, including:
• Using the batch delay to add waiting time between the sets of touch data
• Inserting delays, such as PR and SN (but not PVS), to slow down the coordinate samples within a set
because PR and SN do not consume power
See Table 6 for the bit locations and for the selectable time ranges.
8.2.2.6 Single-Touch Operation
The TSC2013-Q1 device can also be used only for single-touch operation. By measuring all 4-wire nodes (X+,
X–, Y+, Y–) more-precise touch accuracy can be achieved compared to normal resistive TSCs.
TI advises to calculate the center point of the touch by using both node values. Equation 15 shows an example.
X = 0.5 × ([X+] – [X–]) + (X+)
(15)
This same calculation method is used on dual-touch middle-point calculation.
58
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
8.2.3 Application Curves
Touch-Panel Peak Drive Current (mA)
18
Sample 3 Y
Sample 3 X
Sample 3 Z1 and Z2
SNSVDD = 1.6 VDC
SNSVDD = 2.5 VDC
SNSVDD = 3 VDC
SNSVDD = 3.6 VDC
16
14
X+
12
10
X–
8
6
Y+
4
2
0
200
400
600
Y–
800 1000 1200 1400 1600 1800 2000
Panel Resistance (Ω)
Figure 52. Analog Interface Under
ADC Clock = 2 MHz
Figure 51. Touch Panel Power Consumption
Sample 3 Y
Sample 3 X
Sample 3 Z1 and Z2
X+
X+
Sample 3 Y
Sample 3 X
Sample 3 Z1 and Z2
X–
X–
Y+
Y+
PV = 500 µs
PV = 0 µs
PV = 100 µs
Y–
Y–
Figure 54. Panel Voltage Stabilization 0 µs, 100 µs,
and 500 µs
Figure 53. Analog Interface Under
ADC Clock = 1 MHz
Sense time
or SN
Precharge time
or PR
X+
X+
X–
X–
Y+
Y+
Y–
Y–
Figure 55. Precharge Time on TSC Analog Interface Lines
Copyright © 2014, Texas Instruments Incorporated
Figure 56. Sense Time on TSC Analog Interface Lines
Submit Documentation Feedback
59
TSC2013-Q1
SLVSC89A – JUNE 2014 – REVISED JULY 2014
www.ti.com
9 Power Supply Recommendations
The devices are designed to operate from an input voltage supply range between 1.6 V and 3.6 V. Power to the
TSC2013-Q1 device should be clean and well-bypassed. Add a 0.1-μF ceramic bypass capacitor between
(SNSVDD and AGND) or (I/OVDD and AGND).
10 Layout
10.1 Layout Guidelines
The following layout suggestions should obtain optimum performance from the TSC2013-Q1 device. However,
many portable applications have conflicting requirements for power, cost, size, and weight. In general, most
portable devices have fairly clean power and grounds because most of the internal components are very lowpower. This situation would mean less bypassing for the converter power and less concern regarding grounding.
Still, each application is unique, so review the following suggestions carefully.
For optimum performance, take care with the physical layout of the TSC2013-Q1 circuitry. The basic SAR
architecture is sensitive to glitches or sudden changes on the power supply, reference, and ground connections,
and digital inputs that occur just prior to latching the output of the analog comparator. Therefore, during any
single conversion for an n-bit SAR converter, there are n windows in which large external transient voltages can
easily affect the conversion result. Such glitches might originate from switching power supplies, nearby digital
logic, and high-power devices. The degree of error in the digital output depends on the reference voltage, layout,
and the exact timing of the external event. The error can change if the external event changes in time with
respect to the SCL input.
With this in mind, power to the TSC2013-Q1 device should be clean and well-bypassed. Add a 0.1-μF ceramic
bypass capacitor between (SNSVDD and AGND) or (I/OVDD and AGND). The circuit also requires a 0.1-μF
decoupling capacitor between SNSVDD/VREF and AGND. Place these capacitors as close to the device as
possible. The circuit may also require a 1-μF to 10-μF capacitor if the impedance of the connection between
SNSVDD/VREF and the power supply is high. Short I/OVDD to the same supply plane as SNSVDD/VREF. Short
both SNSVDD/VREF and I/OVDD to the analog power-supply plane.
The ADC architecture offers no inherent rejection of noise or voltage variation in regards to using an external
reference input, which is of particular concern when the reference input is tied to the power supply for auxiliary
input. Any noise and ripple from the supply appears directly in the digital results. While high-frequency noise can
be filtered out by the built-in MAV filter, voltage variation as a result of line frequency (50 Hz or 60 Hz) can be
difficult to remove. Avoid any active trace going under the analog pins listed in the table without shielding them
by a ground or power plane.
Connect the AGND pin to a clean ground point. In many cases, this connection will be the analog ground. Avoid
connections that are too near the grounding point of a microcontroller or digital signal processor. If needed, run a
ground trace directly from the converter to the power-supply entry or battery-connection point. The ideal layout
includes an analog ground plane dedicated to the converter and associated analog circuitry.
In the specific case of use with a resistive touch screen, take care with the connection between the converter and
the touch screen. Because resistive touch screens have fairly low resistance, the interconnection should be as
short and robust as possible. Loose connections can be a source of error when the contact resistance changes
with flexing or vibrations.
As indicated previously, noise can be a major source of error in touch-screen applications (for example,
applications that require a backlit LCD panel). This electromagnetic interference (EMI) noise can coupled through
the LCD panel to the touch screen and cause flickering of the converted ADC data. On can do several things to
reduce this error, such as using a touch screen with a bottom-side metal layer connected to ground, which
couples the majority of noise to ground. Another way to filter out this type of noise is by using the TSC2013-Q1
built-in MAV filter (see the section). Filtering capacitors, from Y+, Y–, X+, and X– to ground, can also help. Note,
however, that the use of these capacitors increases screen settling time and requires longer panel voltage
stabilization times, and also increases precharge and sense times for the PINTDAV circuitry of the TSC2013-Q1
device. The resistor value varies depending on the touch-screen sensor used. The internal 50-kΩ pullup resistor
(R(IRQ)) may be adequate for most sensors.
60
Submit Documentation Feedback
Copyright © 2014, Texas Instruments Incorporated
TSC2013-Q1
www.ti.com
SLVSC89A – JUNE 2014 – REVISED JULY 2014
1
2
1
1
1
1
2
1
Bypass Capacitor
R(SENSE) Resistor
Ground Plane
2
1
2
2
1
1
10.2 Layout Example
13
14
16
1
1
12
2
11
1
2
2
1
1
2
4
17
5
1
1
9
2
2
1
1
2
1
2
10
1
3
8
1
7
2
6
1
15
1
1
2
Figure 57. TSC2013-Q1 Layout Example
11 Device and Documentation Support
11.1 Trademarks
All trademarks are the property of their respective owners.
11.2 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
11.3 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the mostcurrent data available for the designated devices. This data is subject to change without notice and without
revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
Copyright © 2014, Texas Instruments Incorporated
Submit Documentation Feedback
61
PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
TSC2013QPWRQ1
ACTIVE
TSSOP
PW
16
2000
RoHS & Green
NIPDAU
Level-3-260C-168 HR
-40 to 125
TS2013Q
TSC2013QRSARQ1
ACTIVE
QFN
RSA
16
2500
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
TSC
2013Q
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of