IQS127D Datasheet
IQ Switch® - ProxSense® Series
Single Channel Capacitive Proximity/Touch Controller
The IQS127D ProxSense® IC is a fully integrated capacitive sensor with dual outputs (Touch
and Proximity outputs).
Features
Automatic Tuning Implementation (ATI) - Automatic adjustment for optimal performance.
Internal Capacitor Implementation (ICI) – reference capacitor on-chip
Supply voltage: 2.95V to 5.5V
RoHS2
Minimum external components
Compliant
Data streaming option
Advanced on-chip digital signal processing
User selectable (OTP): 4 Power Modes (15uA min)
IO sink / source
Time-out for stuck key
Output mode (Direct / Latch / Toggle)
Proximity and Touch Button sensitivity
6 pin TSOT23-6
eq
ot7D
AIzQS12
Representations only,
not actual markings
Keys:
Touch:
Proximity:
Dielectric: Material:
Thickness:
5mm x 5mm or larger (overlay thickness dependent)
Various electrical options (wire / PCB trace / ITO / conductive foil)
Various non-metal materials (i.e. glass, plastic, painted surfaces)
6 mm plastic, 10 mm glass
Applications
LCD, Plasma & LED TVs
GSM cellular telephones – On ear detection /
touch keys
LED flashlights or headlamps
White goods and appliances
Office equipment, toys, sanitary ware
Flame proof, hazardous environment Human
Interface Devices
Proximity detection enables backlighting
activation
Wake-up from standby applications
Replacement for electromechanical switches
Find-In-The-Dark (FITD) applications
Automotive: Door pocket lighting, electric
window control
GUI trigger on Proximity detected
Available options
TA
-40°C to 85°C
TSOT23-6
IQS127D
IQ Switch®
ProxSense® Series
Contents
IQS127D DATASHEET .................................................................................................................................................. 1
1
OVERVIEW ......................................................................................................................................................... 3
2
ANALOGUE FUNCTIONALITY............................................................................................................................... 3
3
PACKAGING AND PIN-OUT ................................................................................................................................. 4
4
USER CONFIGURABLE OPTIONS .......................................................................................................................... 5
5
MEASURING CAPACITANCE USING THE CHARGE TRANSFER METHOD ................................................................ 7
6
DESCRIPTIONS OF USER OPTIONS ...................................................................................................................... 7
7
1-WIRE DATA STREAMING MODE......................................................................................................................11
8
ANTENNA TUNING IMPLEMENTATION (ATI)......................................................................................................13
9
ELECTRICAL SPECIFICATIONS .............................................................................................................................15
10
DATASHEET AND PART-NUMBER INFORMATION ..............................................................................................21
Copyright © Azoteq (Pty) Ltd 2019
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IQS127D Datasheet
Version 1.15
Page 2 of 24
May 2019
IQ Switch®
ProxSense® Series
1 Overview
The IQS127D is a single channel capacitive
proximity and touch device which employs
an internal voltage regulator and reference
capacitor (Cs).
The IQS127D device has a dedicated pin for
the connection of a sense antenna (Cx) and
output pins for proximity events on POUT
and touch events on TOUT. The output pins
can be configured for various output
methods including a serial data streaming
option on TOUT.
Device configuration is determined by one
time programmable (OTP) options.
The devices automatically track slow varying
environmental changes via various filters,
detect noise and has an automatic Antenna
Tuning Implementation (ATI) to tune the
device to the sense antenna.
1.1 Applicability
All specifications, except where specifically
mentioned otherwise, provided by this
datasheet are applicable to the following
ranges:
Temperature:-40C to +85C
Supply voltage (VDDHI): 2.95V to 5V
2 Analogue Functionality
The analogue circuitry measures the
capacitance of a sense antenna attached to
the Cx pin through a charge transfer process
(refer to section 5) that is periodically
initiated by the digital circuitry.
The
measuring process is referred to a
conversion and consists of the discharging
of reference capacitor and Cx, the charging
of Cx and then a series of charge transfers
from Cx to Cs until a trip voltage is reached.
The number of charge transfers required to
reach the trip voltage is referred to as the
current sample (CS).
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The capacitance measurement circuitry
makes use of an internal Cs and voltage
reference (VREF).
The analogue circuitry further provides
functionality for:
Power on reset (POR) detection.
Brown out detection (BOD).
Detection of a watch dog timer (WDT)
expiry.
IQS127D Datasheet
Version 1.15
Page 3 of 24
May 2019
IQ Switch®
ProxSense® Series
3 Packaging and Pin-out
The IQS127D is available in a TSOT23-6 package.
3.1 Pin-out
1
VSS
2
POUT
3
Figure 3.1
Table 3.1
IQS127D
TOUT
6
CX
5
VDDHI
4
VREG
Pin-out of IQS127D package
Pin-out description
IQS127D
Pin
Name
1
2
3
4
5
6
Type
TOUT
VSS
POUT
VREG
VDDHI
CX
Digital Out
Ground
Digital Out
Analogue Output
Supply Input
Analogue I/O
3.1.2 Schematic
Component
DC Supply Input
Sense Antenna
CX
Rcx
C VDDHI
VREG
1uF
470 Ω (typical)
1uF
Proximity Output Pin
POUT
VSS
CVREG
RCX
CVDDHI
Value
Touch Output Pin
TOUT
CVDDHI is optional for
added IC stability
Touch Output
GND Reference
Proximity Output
Internal Regulator Pin
Supply Voltage Input
Sense Antenna
3.1.3 Typical values
IQS127D
VDDHI
Function
Keep track as
short as possible
CVREG
GND
A 100 pF capacitor can be placed in parallel with the
existing capacitors between VDDHI and GND as well
as between VREG and GND for added RF immunity
GND
Figure 3.2
Typical application
schematic of IQS127D.
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IQS127D Datasheet
Version 1.15
Page 4 of 24
May 2019
IQ Switch®
ProxSense® Series
4 User Configurable Options
The IQS127D provides One Time Programmable (OTP) user options (each option can be
modified only once). The device is fully functional in the default (unconfigured) state. OTP
options are intended for specific applications.
The configuration of the device can be done on packaged devices or in-circuit. In-circuit
configuration may be limited by values of external components chosen.
A number of standard device configurations are available (refer to Table 10.1). Azoteq can
supply pre-configured devices for large quantities.
4.1 Configuring of Devices
Azoteq offers a Configuration Tool (CTxxx) and accompanying software (USBProg.exe) that can
be used to program the OTP user options for prototyping purposes. More details regarding the
configuration of the device with the USBProg program is explained by application note: “AZD007
– USBProg Overview” which can be found on the Azoteq website.
Alternate programming solutions of the IQS127D also exist. For further enquiries regarding this
matter please contact Azoteq at ProxSenseSupport@azoteq.com or the local distributor.
TTHR1
TTHR0
Table 4-1: User Selectable Configuration Options: Bank 0
PTHR1
PTHR0
FUNC1
FUNC0
LOGIC
~
bit 7
bit 0
Bank 1: bit 0,
Bank 0: bit 7-6
TTHR: Touch Thresholds
-Section 6.4
000 = 1/16
001 = 1/32
010 = 2/16
011 = 3/16
100 = 4/16
101 = 6/16
110 = 8/16
111 = 10/16
Bank0: bit 5-4
PTHR: Proximity Thresholds
00 = 2
01 = 4
10 = 8
11 = 16
-Section 6.3
Bank0: bit 3-2
FUNC: OUTPUT Pins’ functions
00 = POUT active, TOUT active
01 = POUT latch, TOUT active
10 = POUT active, TOUT toggle
11 = POUT latch, TOUT toggle
-Section 6.2
Bank0: bit 1
LOGIC: Output logic select 0 = Active Low
1 = Active High
-Section 6.1
Bank0: bit 0
Not Used
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IQS127D Datasheet
Version 1.15
Page 5 of 24
May 2019
IQ Switch®
ProxSense® Series
STREAMING
Table 4-2: User Selectable Configuration Options: Bank 1
SHORT
tHALT1
tHALT0
PMODE1
PMODE0
STREAMING
TTHR2
bit 7
bit 0
Bank 1: bit 7
STREAMING: 1-wire streaming mode
0 = disabled
1 = enabled
Bank1: bit 6
Not used
Bank1: bit 5
SHORT STREAMING: Short word streaming enable
(Function enabled if this bit together with STREAMING bit is set) –Section 7
-Section 7
Bank1: bit 4-3
tHALT: Halt time of Long Term Average
00 = 18.6 seconds
01 = 74.5 seconds
10 = Never
11 = Always
-Section 6.6
Bank1: bit 2-1
PMODE:Power Modes
00 = Boost Mode
01 = Normal Power Mode
10 = Low Power Mode 1
11 = Low Power Mode 2
-Section 6.5
Bank1: bit 0
TTHR: Touch Thresholds
See Table 4-1
-Section 6.4
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IQS127D Datasheet
Version 1.15
Page 6 of 24
May 2019
IQ Switch®
ProxSense® Series
5 Measuring capacitance using the Charge Transfer method
The charge transfer method of capacitive
sensing is employed on the IQS127D. (The
charge transfer principle is thoroughly
described in the application note: “AZD004 Azoteq Capacitive Sensing”.)
A charge cycle is used to take a measurement
of the capacitance of the sense antenna
(connected to Cx) relative to ground. It
consists of a series of pulses charging Cx and
discharging Cx to the reference capacitor, at
the charge transfer frequency (FCX - refer to
Section 9). The count of the pulses required
to reach a trip voltage on the reference
capacitor is referred to as a current sample
(CS) which is the instantaneous capacitive
measurement. The CS is used to determine if
either a physical contact or proximity event
occurred (refer to section 6.6.1), based on the
change in CS detected. The typical values of
CS, without a touch or proximity condition
range between 650 and 1150, although
higher and lower counts can be used based
on the application requirements. With CS
larger than +/-1150 the gain of the system
may become too high causing unsteady
current samples.
The IQS127D schedules a charge cycle every
tSAMPLE seconds to ensure regular samples for
processing of results. The duration of the
charge cycle is defined as tCHARGE. (refer
toFigure 5.1) and varies according to the
counts required to reach the trip voltage.
Following the charge cycle other activities
such as data streaming is completed (if in
streaming mode), before the next charge
cycle is initiated.
Please note: Attaching a probe to the Cx
pin will increase the capacitance of the
sense plate and therefore CS. This may
have an immediate influence on CS
(decrease tCHARGE – thus CS) and cause a
proximity or touch event. After tHALT
seconds the system will adjust to
accommodate for this change. If the total load
on Cx, with the probe attached is still lower
than the maximum Cx load the system will
continue to function normally after tHALT
seconds with the probe attached.
t
SAMPLE
t
CHARGE
Cx pin
1
Figure 5.1
6
2
3
4
Charge cycles as can be seen on Cx.
Descriptions of User Options
This section describes the individual user
programmable options of the IQS127D in
more detail.
User programmable options are programmed
to One Time Programmable (OTP) fuse
registers.
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Note:
HIGH=Logical ‘1’ and LOW=Logical ‘0’.
The following sections are explained with
the OUT, POUT and TOUT taken as ‘Active
LOW’.
The default is always where bits are set to
0.
IQS127D Datasheet
Version 1.15
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May 2019
IQ Switch®
ProxSense® Series
Refer to section 9.3 for the sourcing and
sinking capabilities of OUT, POUT and TOUT.
These pins are sourced from VDDHI and will be
turned HIGH (when active high) for a
minimum time of tHIGH, and LOW for a
minimum time of tLOW (when active low).
6.1
Logic select for output(s)
The logic used by the device can be selected
as active HIGH or active LOW. The output
pins POUT, TOUT and OUT will function
based on the selection.
Configuration: Bank0 bit1
LOGIC: Output logic select Bit
Selection
0
Active Low
1
Active High
6.2
Configuration: Bank0 bit2-3
FUNC1:FUNC0 OUTPUT Pins’ functions
IQS127D
Bit
Selection
00
POUT active, TOUT active
01
POUT latch, TOUT active
10
POUT active, TOUT toggle
11
POUT latch, TOUT toggle
6.2.1 Output function: Active
With a Proximity or Touch event, the output
pin will change to LOW and stay LOW for as
long as the event remains (see Figure 6.1).
Also refer to the use of tHALT section 6.6.1 that
may cause the termination of the event.
Output pin function
Various options for the function of the output
pin(s) are available. These are selected as
follow:
User Actuation
1
0
Output Pin
1
0
Figure 6.1
Active Mode Output Configuration
6.2.2 Output function: Latch (for tLATCH)
With a Proximity or Touch event, the output
pin will latch LOW for tLATCH seconds.
When the event remains active longer than
tLATCH the output pin will remain LOW as long
as the event remains active (see Figure 6.2).
When the event terminates prior to tLATCH the
output pin will remain LOW.
User Actuation
1
0
Output Pin
tLATCH
tLATCH
tLATCH
+ time that User Actuation stays active
1
0
Figure 6.2
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Latch Mode Output Configuration
IQS127D Datasheet
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May 2019
IQ Switch®
ProxSense® Series
6.2.3 Output function: Toggle
The touch output pin will toggle with every
Touch event occurring. Thus when an event
occurs and the output is LOW the output will
become HIGH and when the output is HIGH the
output will become LOW (see Figure 6.3).
User Actuation
1
0
Output Pin
1
0
Figure 6.3
6.3
Toggle Mode Output Configuration
Proximity Threshold
The IQS127D has 4 proximity threshold
settings. The proximity threshold is selected by
the designer to obtain the desired sensitivity and
noise immunity.
The proximity event is
triggered based on the selected proximity
threshold; the CS and the LTA (Long Term
Average). The threshold is expressed in terms
of counts; the same as CS (refer to Section 5).
Configuration: Bank0 bit4-5
PTHR1:PTHR0 Proximity Thresholds
Bit
Selection
00
2 (Most sensitive)
01
4
10
8
11
16 (Least sensitive)
A proximity event is identified when for at least
6 consecutive samples the following equation
holds:
at least 3 consecutive samples the following
equation holds:
TTH =< LTA-CS
With lower average CS (therefore lower LTA)
values the touch threshold will be lower and
vice versa.
Configuration: Bank0 bit6-7 and Bank1
bit0TTHR2:TTHR0: Touch Thresholds
TTHR2:TTHR0 Proximity Thresholds
Bit
Selection
000 1/16
001 1/32 (Most sensitive)
010 2/16
011 3/16
100 4/16
101 6/16
110 8/16
111 10/16 (Least sensitive)
PTHR =< LTA-CS
Where LTA is the Long Term Average (refer to 6.6.1)
6.4
Touch Threshold
The IQS127D has 8 touch threshold settings.
The touch threshold is selected by the
designer to obtain the desired touch
sensitivity. The touch threshold is expressed
as a fraction of the LTA as follows:
TTHR = Selected Touch Threshold x LTA
Where LTA is the Long Term Average (refer to 6.6.1)
The touch event is triggered based on TTH, CS
and LTA. A touch event is identified when for
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IQS127D Datasheet
Version 1.15
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May 2019
IQ Switch®
ProxSense® Series
PROXIMITY threshold measured as Current Sample value:
Most
A
B
D
C
Sensitive
2
4
8
Default Proximity threshold = 2
16
1/32
Figure 6.4
6.5
TOUCH threshold measured as Fraction of Current Sample:
I
F
G
H
K
J
E
The IQS127D IC has four power modes
specifically designed to reduce current
consumption for battery applications.
The power modes are basically implemented
around the occurrence of charge cycle every
tSAMPLE seconds (refer to Section 5). The
fewer charge transfer cycles that need to
occur per second the lower the power
consumption (but decreased response time).
During Boost Power Mode (BP), charge
cycles are initiated approximately every 9ms.
Additional Power Modes are provided. While in
any power mode the device will zoom to BP
Charge Cycle
Duration = tCHARGE
tSAMPLE
10/16
whenever a current sample (CS) indicates a
possible proximity or touch event. The device
will remain in BP for tZOOM seconds and then
return to the selected power mode. The Zoom
function allows reliable detection of events
with current samples being produced at the
BP rate.
Table 6-1: Power Mode configuration (Bank1
bit[3:2])
Bit
Power Mode timing
tSAMPLE (ms)
00
tBP (default)
BP (9ms)
01
tNP
50
10
tLP1
100
11
tLP2
200
tSAMPLE
LP Modes: Charge cycles
Filters used by the IQS127D
The IQS127D device employs various signal
processing functions that includes the
execution of various filters as described
below.
6.6.1 Long Term Average (LTA)
Capacitive touch devices detect changes in
capacitance that are not always related to the
intended proximity or touch of a human. This
is a result of changes in the environment of
the sense plate and other factors. These
changes need to be compensated for in
various manners in order to reliably detect
touch events and especially to detect
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8/16
Zoom to Boost Mode after proximity detected
Figure 6.5
6.6
2/16
3/16 4/16
6/16
Default Touch threshold = 1/16
Least
Sensitive
Proximity and Touch Thresholds.
Power Modes
CX
1/16
L
proximity events.
One mechanism the
IQS127D employs is the use of a Long Term
Averaging filter (IIR - Infinite Impulse
Response - type filter) which tracks slow
changes in the environment (expressed as
changes in the current sample). The result of
this filter is a Long Term Average (LTA) value
that forms a dynamic reference used for
various functions such as identification of
proximity and touch events.
The LTA is calculated from the current
samples (CS). The filter only executes while
no proximity or touch event is detected to
ensure compensation only for environmental
changes. However there may be instances
where sudden changes in the environment or
IQS127D Datasheet
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May 2019
IQ Switch®
ProxSense® Series
changes in the environment while a proximity
or touch event has been detected cause the
CS to drift away from the LTA. To compensate
for these situations a Halt Timer (tHALT) has
been defined.
The Halt Timer is started when a proximity or
touch event occurs and when it expires the
LTA filter is recalibrated. Recalibration causes
LTA < CS, thus the disappearance of
proximity or touch events (refer to Section 6.3
and Section 6.4).
The designer needs to select a Halt Timer
value to best accommodate the required
application.
Configuration: Bank1 bit4-3
tHALT1:tHATL0: Halt time of Long Term Average
Bit
Selection
00
18.6 seconds
01
74.5 seconds
10
NEVER
11
ALWAYS
Notes:
The “NEVER” option indicates that the
execution of the filters will never be halted.
With the ‘ALWAYS’ option and the detection
of a proximity event the execution of the filter
will be halted for only 18.6 seconds and with
the detection of a touch event the execution
of the filter will be halted as long as the touch
condition applies.
Refer to Application note “AZD024 - Graphical
Representation of the IIR Filter” for detail
regarding the execution of the LTA filter.
6.6.2 IIR Raw Data filter
The extreme sensitivity of the IQS127D
makes it susceptible to external noise
sources. This causes a decreased signal to
noise (S/N) ratio, which could potentially
cause false event detections.
Noise can also couple into the device as a
result of poor PCB, sense antenna design and
other factors influencing capacitive sensing
devices.
In order to compensate for noise the IQS127D
uses an IIR filter on the raw data to minimize
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result of noise in the current sample. This filter
cannot be disabled.
7 1-Wire
Mode
Data
Streaming
The IQS127D has the capability to stream
data to a MCU. This provides the designer
with the capability to obtain the parameters
within the device in order to aid design into
applications. Data streaming may further be
used by a MCU to control events or further
process results obtained from the IQS127D
devices. Data streaming is performed as a 1wire data protocol on one of the output pins
(TOUT). The function of this pin is therefore
lost when the device is put in streaming mode.
Data Streaming can be enabled as indicated
below:
Configuration: Bank1 bit7
STREAMING: 1-wire data streaming mode
Bit
Selection
0
Disabled
1
Enabled
The IQS127D has a short data streaming
mode where a reduced set of data is
streamed to the MCU. This option can be
used only when data streaming has been
activated.
Configuration: Bank1 bit5
SHORT STREAMING: Short data streaming
Bit
Selection
0
Disabled
1
Enabled
Data streaming is initiated by the IQS127D.
When data streaming is enabled data is sent
following each charge cycle (refer to Section
5).
Figure 7.1 illustrates the communication
protocol for initialising and sending data with
the 1 wire communication protocol.
1. Communication is initiated by a START
bit. Bit defined as a low condition for
tSTART.
2. Following the START bit, is a
synchronisation byte (TINIT = 0xAA).
IQS127D Datasheet
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May 2019
IQ Switch®
ProxSense® Series
4. Each byte sent will be preceded by a
START bit and a STOP bit will follow
every byte.
5. STOP bit indicated by taking pin 1 high.
The STOP bit does not have a defined
period.
This byte is used by the MCU for clock
synchronisation.
3. Following TINIT the data bytes will be
sent. With short data streaming mode
enabled, 5 bytes of data will be sent,
otherwise 8 bytes will be sent after each
charge cycle.
TOUT
/OUT
D7
tINIT
tDATA
D6
D5
D4
D3
D2
D1
D0
tSTOP
Stop – Start
Start
Stop – Start
Figure 7.1
1-wire data streaming mode
The following tables define the data streamed
from the IQS127D devices during Short Data
Streaming and Normal Data Streaming
modes.
Table 7.1
Byte Definitions for Short
Data Streaming Mode
Byte
0
1
2
3
4
Bit
7:0
15:8
23:16
31:24
39
35:32
Value
Current sample High byte
Current sample Low byte
LTA High byte
LTA Low byte
Proximity event detected
Touch event detected
Not used (always 0)
Zoom active
Non-user data
Table 7.2
Byte Definitions for Normal
Data Streaming Mode
Byte
0
1
2
3
4
5
6
7
Bit
7:0
15:8
23:16
31:24
39
38
37
36
35
34
33
32
47
46
45
44
43
42
41
40
55:48
63:56
Value
CS High byte
CS Low byte
LTA High byte
LTA Low byte
ATI busy
Compensation (P5)
PTH0 – Proximity threshold
PTH1 – Proximity threshold
Not used (always 0)
Zoom active
Touch event detected
Proximity event detected
ATI Multiplier (I)
ATI Multiplier (S)
ATI Multiplier (S)
Compensation (P4)
Compensation (P3)
Compensation (P2)
Compensation (P1)
Compensation (P0)
Non-user data
Counter
Azoteq provides an application tool (GUI) that
can be utilised to capture and visualise the
data streamed from the IQS127D. Refer to the
Azoteq website for more details.
Normal 1-wire data streaming mode is used
when all data is required from IC. Short 1-wire
data streaming mode is used when only
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IQS127D Datasheet
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May 2019
IQ Switch®
ProxSense® Series
instantaneous measurement and Prox/Touch
events are needed.
Sample code available: “AZD017 - IQS127D
1-Wire Protocol SAMPLE CODE”
8 Antenna
Tuning
Implementation (ATI)
ATI
is
a
sophisticated
technology
implemented in the latest generation
ProxSense® devices that optimises the
performance of the sensor in a wide range of
applications and environmental conditions
(refer to application note AZD0027 - Antenna
Tuning Implementation).
ATI makes adjustments through external
reference capacitors (as required by most
other
solutions)
to
obtain
optimum
performance.
ATI adjusts internal circuitry according to two
parameters, the ATI multiplier and the ATI
compensation. The ATI multiplier can be
viewed as a course adjustment and the ATI
compensation as a fine adjustment.
The adjustment of the ATI parameters will
result in variations in the current sample and
sensitivity. Sensitivity can be observed as the
change in current sample as the result of a
fixed change in sensed capacitance. The ATI
parameters have been chosen to provide
significant overlap. It may therefore be
possible to select various combinations of ATI
multiplier and ATI compensation settings to
obtain the same current sample. The
sensitivity of the various options may however
be different for the same current sample.
While the automatic ATI algorithm is in
progress this condition will be indicated in the
streaming data, and proximity and touch
events cannot be detected. The device will
only briefly remain in this condition and it will
be entered only when relatively large shifts in
the current sample has been detected.
The automatic ATI function aims to maintain
a constant current sample, regardless of the
capacitance of the sense antenna (within the
maximum range of the device).
The effects of auto-ATI on the application are
the following:
8.1 Automatic ATI
The IQS127D implements an automatic ATI
algorithm. This algorithm automatically
adjusts the ATI parameters to optimise the
sensing antenna’s connection to the device.
The device will execute the ATI algorithm
whenever the device starts-up and when the
current samples are not within a
predetermined range.
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Automatic adjustment of the device
configuration and processing parameters for
a wide range of PCB and application
designs to maintain an optimal configuration
for proximity and touch detection.
Automatic tuning of the sense antenna at
start-up to optimise the sensitivity of the
application.
Automatic re-tuning when the device
detects changes in the sensing antenna’s
capacitance to accommodate a large range
of changes in the environment of the
application that influences the sensing
antenna.
Re-tuning only occurs during device
operation when a relatively large sensitivity
reduction is detected. This is to ensure
smooth operation of the device during
operation.
Re-tuning may temporarily influence the
normal functioning of the device, but in most
instances the effect will be hardly
noticeable.
Shortly after the completion of the re-tuning
process the sensitivity of a proximity
detection may be reduced slightly for a few
seconds as internal filters stabilise.
Automatic ATI can be implemented effectively
due to:
Excellent system signal to noise ratio
(SNR).
Effective digital signal processing to remove
AC and other noise.
The very stable core of the devices.
IQS127D Datasheet
Version 1.15
Page 13 of 24
May 2019
IQ Switch®
ProxSense® Series
The built in capability to accommodate a
large
range
of
sensing
antenna
capacitances.
8.2 Noise Immunity
The IQS127D has advanced immunity to RF
noise sources such as GSM cellular
telephones, DECT, Bluetooth and WIFI
devices. Design guidelines should however
be followed to ensure the best noise
immunity. The design of capacitive sensing
applications can encompass a large range of
situations but as a summary the following
should be noted to improve a design:
A ground plane should be placed under the
IC, except under the Cx line.
All the tracks on the PCB must be kept as
short as possible.
The capacitor between VDDHI and VSS as well
as between VREG and VSS, must be placed
as close as possible to the IC.
A 100 pF capacitor can be placed in parallel
with the 1uF capacitor between VDDHI and
VSS. Another 100 pF capacitor can be
placed in parallel with the 1uF capacitor
between VREG and VSS.
When the device is too sensitive for a
specific application a parasitic capacitor
(max 5pF) can be added between the Cx
line and ground.
Proper sense antenna and button design
principles must be followed.
Unintentional coupling of sense antenna to
ground and other circuitry must be limited by
increasing the distance to these sources or
making use of the driven shield.
In some instances a ground plane some
distance from the device and sense antenna
may provide significant shielding from
undesired interference.
When the capacitance between the sense
antenna and ground becomes too large the
sensitivity of the device may be influenced.
Copyright © Azoteq (Pty) Ltd 2019
All rights reserved
IQS127D Datasheet
Version 1.15
Page 14 of 24
May 2019
IQ Switch®
ProxSense® Series
9
Electrical Specifications
9.1
Absolute Maximum Specifications
Exceeding these maximum specifications may cause damage to the device.
Operating temperature
Supply Voltage (VDDHI – VSS)
Maximum pin voltage (OUT, TOUT, POUT)
Pin voltage (Cx)
Minimum pin voltage (VDDHI, VREG, OUT, TOUT, POUT, Cx)
Minimum power-on slope
HBM ESD protection1 (VDDHI, VREG, VSS, TOUT/OUT, POUT/SHLD, Cx)
9.2
General Characteristics (Measured at 25°C)
Table 9.1
IQS127D General Operating Conditions
DESCRIPTION
Supply voltage
Internal regulator output
Boost operating current
Normal operating current
Low power operating current
Low power operating current
Table 9.2
Conditions
2.95 ≤ VDDHI ≤ 5.0
2.95 ≤ VDDHI ≤ 5.0
2.95 ≤ VDDHI ≤ 5.0
2.95 ≤ VDDHI ≤ 5.0
2.95 ≤ VDDHI ≤ 5.0
PARAMETER
VDDHI
VREG
IIQS127D BP
IIQS127D NP
IIQS127D LP1
IIQS127D LP2
MIN
2.95
2.35
TYP
2.50
60
23
17
13
MAX
5.50
2.65
77
29
22
17
UNIT
V
V
μA
μA
μA
μA
Start-up and shut-down slope Characteristics
DESCRIPTION
POR
BOD
VDDHI safe
reset
1
-40°C to 85°C
5.5V
VDDHI + 0.5V
2.5V
VSS - 0.5V
100V/s
2kV
Conditions
PARAMETER
VDDHI Slope ≥ 100V/s
POR
VDDHI Slope ≥ 100V/s
BOD
DC-level (not transient
RESET ensure
slope dependent)
MIN
1.45
1.30
0.6
MAX
1.70
1.40
UNIT
V
V
V
See Section 9.4.1 for further details
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IQS127D Datasheet
Version 1.15
Page 15 of 24
May 2019
IQ Switch®
ProxSense® Series
9.3
Output Characteristics (Measured at 25°C)
Table 9.3
TOUT Characteristics
Symbol
Description
VOH
Output High
voltage
Symbol
Description
VOL
Output
voltage
Table 9.4
Low
ISOURCE (mA)
1
1
1
ISINK (mA)
1
1
1
Conditions
VDDHI = 5V
VDDHI = 3.3V
VDDHI = 2.5V
Conditions
VDDHI = 5V
VDDHI = 3.3V
VDDHI = 2.5V
MIN
MIN
0.30
0.20
0.20
TYP
4.5
2.97
2.25
TYP
0.50
0.33
0.25
MAX
TYP
4.5
2.97
2.25
TYP
0.5
0.33
0.25
MAX
UNIT
V
MAX
UNIT
V
POUT Characteristics
Symbol
Description
VOH
Output High
voltage
Symbol
Description
VOL
Output
voltage
Low
Copyright © Azoteq (Pty) Ltd 2019
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ISOURCE (mA)
5.0
2.5
2.5
ISINK (mA)
3.0
2.5
2.5
Conditions
VDDHI = 5V
VDDHI = 3.3V
VDDHI = 2.5V
Conditions
VDDHI = 5V
VDDHI = 3.3V
VDDHI = 2.5V
MIN
MIN
0.1
0.1
0.1
IQS127D Datasheet
Version 1.15
UNIT
V
MAX
UNIT
V
Page 16 of 24
May 2019
IQ Switch®
ProxSense® Series
9.4
Electromagnetic Compatibility
9.4.1 Electrostatic discharge (ESD)
Table 9.5
ESD Characteristics
Symbol
Ratings
Conditions
VESD(HBM)
Electrostatic discharge voltage
(Human body model)
VESD(CDM)
Electrostatic discharge voltage
(Charge device model)
VESD(Product)
Electrostatic discharge voltage
(Product specification)1
VESD(Product)
Electrostatic discharge voltage
(Product specification)1
TA = +25°C,
conforming to
JESD22-A114
TA = +25°C,
conforming to
JESD22-C101-D
TA = +25°C,
conforming to
IEC61000-4-2, Airdischarge on all pins
TA = +25°C,
conforming to
IEC61000-4-2,
Contact-discharge on
all pins
Level/
Class
Maximum
Value
UNIT
2
2000
V
IV
1000
V
4
±8
kv
3
±6
kv
9.4.2 Static Latch-Up (LU)
Table 9.6
Static Latch-Up (LU)
Class
Symbol
A
LU
Parameter
Static latch-up class
Conditions
TA = +25°C, conforming to
EIA/JESD 78 IC latch-up
standard
For further details on test results please request from Azoteq.
Product specification is dependent on PCB layout. Test performed on standard AZP112A05 product
PCB plugged into the AZP113A03 touchpad PCB, powered with a single 3.0V coin-cell.
1
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IQS127D Datasheet
Version 1.15
Page 17 of 24
May 2019
IQ Switch®
ProxSense® Series
9.5
Timing Characteristics
Table 9.7
SYMBOL
FOSC
Table 9.8
SYMBOL
tHIGH
tLOW
FCX
tLATCH
tCHARGE
tSAMPLE
tBP
tBP
tSTART
tINIT
tDATA
tNP
tLP1
tLP2
tZOOM
1
Main Oscillator NP mode1
DESCRIPTION
IQS127D Main oscillator
Conditions
2.95 ≤ VDDHI ≤ 5.0
MIN
0.9
TYP
1
MAX
1.1
UNIT
MHz
MAX
UNIT
General Timing Characteristics for 2.95V ≤ VDDHI ≤ 5.0V
DESCRIPTION
Output high minimum
time
Output low minimum
time
Charge transfer
frequency
OUT high time in latch
mode (active high)
Charge cycle duration
Refer to section 5
Sampling period in BP
Sampling period in BP
Refer to section 7
Refer to section 7
Refer to section 7
Sampling period in NP
Sampling period in LP1
Sampling period in LP2
Period in BP after
possible event
Conditions
MIN
TYP
9
ms
9
ms
125
kHz
4.6
sec
CS = 900
7.2
tCHARGE - 2 ≤ tSAMPLE
tCHARGE ≥ tSAMPLE
9
ms
ms
ms
ms
us
us
us
ms
ms
ms
14.4
tCHARGE+2
17
136
136
50
100
200
4.6
18.8
s
All timings are derived from the main oscillator.
Copyright © Azoteq (Pty) Ltd 2019
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IQS127D Datasheet
Version 1.15
Page 18 of 24
May 2019
IQ Switch®
ProxSense® Series
Table 9.9
IQS127D Response Times
Proximity
Min
Max
54
63
95
145
145
245
245
445
Touch
Typical
250
120
Power Mode
Boost Power
Normal Power
Low Power 1
Low Power 2
Power Mode
All
All
9.6
IC Batch #
Unit
ms
ms
ms
ms
Unit
ms
ms
All
All
All
All
IC Batch #
Up to 127DBD
From 127DBx
Packaging Information
9.6.1 TSOT23-6
C
A
B
D
E
F
J
G
I
H
Figure 9.1
Table 9.10
TSOT23-6 Packaging1
TSOT23-6 Dimensions
A
B
C
D
E
F
G
H
I
J
Dimension
Typical
2.80 mm
1.60 mm
2.90 mm
0.40 mm
0.95 mm
1.00mm
0.05 mm
0.40 mm
4
0.127 mm
Tolerance
Basic
Basic
Basic
±0.10mm
Basic
Max
±0.05mm
±0.10mm
±4°
+0.07/-0.007
9.6.2 TSOT23-6 Tape
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IQS127D Datasheet
Version 1.15
Page 19 of 24
May 2019
IQ Switch®
ProxSense® Series
Figure 9.2
IQS127D Tape Specification
9.7 Package MSL
Moisture Sensitivity Level (MSL) relates to the packaging and handling precautions for some
semiconductors. The MSL is an electronic standard for the time period in which a moisture
sensitive device can be exposed to ambient room conditions (approximately 30°C/60%RH).
Increasingly, semiconductors have been manufactured in smaller sizes. Components such as
thin fine-pitch devices and ball grid arrays could be damaged during SMT reflow when moisture
trapped inside the component expands.
The expansion of trapped moisture can result in internal separation (delamination) of the plastic
from the die or lead-frame, wire bond damage, die damage, and internal cracks. Most of this
damage is not visible on the component surface. In extreme cases, cracks will extend to the
component surface. In the most severe cases, the component will bulge and pop.
Table 9-1: MSL
Package
TSOT23-6
1
Level (duration)
MSL 1 ( Unlimited at ≤30 °C/85% RH)
Drawing not on Scale
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IQS127D Datasheet
Version 1.15
Page 20 of 24
May 2019
IQ Switch®
ProxSense® Series
10 Datasheet and Part-number Information
10.1 Ordering Information
Only full reels can be ordered and orders will be subject to a MOQ (Minimum Order Quantity) of
a full reel. Contact the official distributor for sample quantities. A list of the distributors can be
found under the “Distributors” section of www.azoteq.com.
For large orders, Azoteq can provide pre-configured devices.
The Part-number can be generated by using USBProg.exe or the Interactive Part Number
generator on the website.
IQS127y zzzzz pp b
BULK PACAKAGING
IC NAME
CONFIGURATION
PACKAGE TYPE
IC NAME
IQS127D
=
IQS127 with Dual outputs
CONFIGURATION
zzzzz
=
IC Configuration (hexadecimal)
PACKAGE TYPE
TS
=
TSOT23-6
BULK PACKAGING
R
=
Reel (3000pcs/reel) – MOQ = 3000pcs
10.2 Standard Devices
The default (unconfigured) device will be suitable for most applications. Some popular
configurations are kept in stock and do not require further programming. (Ordering codes given
for Device IDs: 03 0D / 03 0E or later (the Device ID will be read in USBProg))
Standard Devices1
IQS127D-00000TSR
IQS127D-00002TSR
IQS127D-00200TSR
IQS127D-00008TSR
1
Function
Default
Active HIGH outputs
Normal Power Mode
Touch Output ac Toggle
All configurations ‘default’ except those mentioned under Function
Copyright © Azoteq (Pty) Ltd 2019
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IQS127D Datasheet
Version 1.15
Page 21 of 24
May 2019
IQ Switch®
ProxSense® Series
Table 10.1
Standard Devices Available
10.3 Device Packaging Convention
10.3.1 Top
127y xx
IC NAME
IC Name
BATCH
BATCH
127D
XX
10.3.2 Bottom
Some batches IQS127D will not have any bottom markings. These devices are configured after
marking, and may have variations in configuration – please refer to the reel label.
Other batches will display the configuration set on the chip on the bottom marking.
zzzzz
Configuration
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IQS127D Datasheet
Version 1.15
Page 22 of 24
May 2019
IQ Switch®
ProxSense® Series
10.4 Datasheet Revision History
Version 1.0
First official release
Version 1.1
Add BOD and POR
Correct formatting errors
Correct minor errors
Version 1.2
Edited version (Final Production release)
Version 1.3
Updated current consumption
Version 1.4
Corrected version number
Fixed Section 10.3
Version 1.4
Fixed bookmarks and added patents on last page
Version 1.6
Updated power mode descriptions and Section 4
Removed EMI test results
Version 1.7
Updated Short and Long 1-Wire protocol data string (removed LTN)
Removed the word ‘debug’ when describing the 1-wire data mode
Added MSL data
Version 1.8
Corrected Section 4.1
Version 1.9
Updated Package dimensions
Updated ESD testing information
Version 1.10
Fix broken references
Version 1.11
Fixed Package Dimensions
Added Tape Specification
Version 1.12
Update package marking
Update Contact Information
Version 1.13 Remove IQS127S (IQS127S is EOL)
Low voltage version no longer available – use IQS227AS instead.
Version 1.14 Update Contact and Patent Information
Version 1.15 Update VDDHI reset voltage condition
Copyright © Azoteq (Pty) Ltd 2019
All rights reserved
IQS127D Datasheet
Version 1.15
Page 23 of 24
May 2019
IQ Switch®
ProxSense® Series
Azoteq
USA
Asia
South Africa
Physical
Address
11940 Jollyville
Suite 120-S
Austin
TX 78750
USA
Room 501A, Block A,
T-Share International Centre,
Taoyuan Road, Nanshan District,
Shenzhen, Guangdong, PRC
1 Bergsig Avenue
Paarl
7646
South Africa
Postal
Address
11940 Jollyville
Suite 120-S
Austin
TX 78750
USA
Room 501A, Block A,
T-Share International Centre,
Taoyuan Road, Nanshan District,
Shenzhen, Guangdong, PRC
PO Box 3534
Paarl
7620
South Africa
Tel
+1 512 538 1995
+86 755 8303 5294
ext 808
+27 21 863 0033
Email
info@azoteq.com
info@azoteq.com
info@azoteq.com
Visit www.azoteq.com
for a list of distributors and worldwide representation.
Patents as listed on www.azoteq.com/patents-trademarks/ may relate to the device or usage of the device.
Azoteq®, Crystal Driver , IQ Switch®, ProxSense®, ProxFusion®, LightSense™, SwipeSwitch™, and the
logo are trademarks of Azoteq.
The information in this Datasheet is believed to be accurate at the time of publication. Azoteq uses reasonable effort to maintain the information up-to-date and accurate, but does
not warrant the accuracy, completeness or reliability of the information contained herein. All content and information are provided on an “as is” basis only, without any representations
or warranties, express or implied, of any kind, including representations about the suitability of these products or informat ion for any purpose. Azoteq disclaims all warranties and
conditions with regard to these products and information, including but not limited to all implied warranties and conditions of merchantability, fitness for a particular purpose, title
and non-infringement of any third party intellectual property rights. Azoteq assumes no liability for any damages or injury arising from any use of the information or the product o r
caused by, without limitation, failure of performance, error, omission, interruption, defect, delay in operation or transmiss ion, even if Azoteq has been advised of the possibility of
such damages. The applications mentioned herein are used solely for the purpose of illustration and Azoteq makes no warranty or representation that such applications will be
suitable without further modification, nor recommends the use of its products for application that may present a risk to human life due to malfunction o r otherwise. Azoteq products
are not authorized for use as critical components in life support devices or systems. No licenses to patents are granted, implicitly, express or implied, by estoppel or otherwise,
under any intellectual property rights. In the event that any of the abovementioned limitations or exclusions does not apply , it is agreed that Azoteq’s total liability for all losses,
damages and causes of action (in contract, tort (including without limitation, negligence) or otherwise) will not exceed the amount already paid by the customer for the products.
Azoteq reserves the right to alter its products, to make corrections, deletions, modifications, enhancements, improvements and other changes to the content and information, its
products, programs and services at any time or to move or discontinue any contents, products, programs or services without pr ior notification. For the most up-to-date information
and binding Terms and Conditions please refer to www.azoteq.com.
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
info@azoteq.com
IQS5xx-B000 Datasheet
Revision 2.1
Page 1 of 1
March 2021