IQ Switch®
ProxSense® Series
Azoteq
IQS127D DATASHEET
Single channel capacitive proximity/touch controller.
The IQS127D ProxSense® IC is a fully integrated capacitive sensor with dual outputs (Touch and
Proximity outputs).
Features
>
>
>
>
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Automatic Tuning Implementation (ATI) - Automatic adjustment for optimal performance.
Internal Capacitor Implementation (ICI) – reference capacitor on-chip
Supply voltage: 2.95V to 5.5V
Minimum external components
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
eq
ot7D
AIzQS12
RoHS2
Compliant
6 pin TSOT23-6
Representations only,
not actual markings
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
>
>
>
>
>
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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 detect
Available options
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
TA
TSOT23-6
-40°C to 85°C
IQS127D
IQS127D Datasheet
Page 1 of 25
Revision 1.16
January 2023
IQ Switch®
ProxSense® Series
Azoteq
Contents
OVERVIEW................................................................................................................................................ 3
ANALOGUE FUNCTIONALITY ................................................................................................................ 3
PACKAGING AND PIN-OUT .................................................................................................................... 4
USER CONFIGURABLE OPTIONS ......................................................................................................... 5
MEASURING CAPACITANCE USING THE CHARGE TRANSFER METHOD ....................................... 7
DESCRIPTIONS OF USER OPTIONS ..................................................................................................... 7
1-WIRE DATA STREAMING MODE ....................................................................................................... 11
ANTENNA TUNING IMPLEMENTATION (ATI) ...................................................................................... 13
ELECTRICAL SPECIFICATIONS ........................................................................................................... 15
DATASHEET AND PART-NUMBER INFORMATION ........................................................................... 22
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 2 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Overview
The IQS127D is a single channel capacitive
proximity and touch device which employs an
internal voltage regulator and reference
capacitor (Cs).
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.
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.
Applicability
All specifications, except where specifically
mentioned otherwise, provided by this
datasheet are applicable to the following
ranges:
Device configuration is determined by onetime programmable (OTP) options.
Keys:
Touch:
Proximity:
Dielectric:
Material:
Thickness:
>
>
Temperature: -40C to +85C
Supply voltage (VDDHI): 2.95V to 5V
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
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).
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
The capacitance measurement circuitry
makes use of an internal Cs and voltage
reference (VREF).
The analogue circuitry
functionality for:
further
provides
> Power on reset (POR) detection.
> Brown out detection (BOD).
> Detection of a watch dog timer (WDT)
expiry.
IQS127D Datasheet
Revision 1.16
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January 2023
Azoteq
IQ Switch®
ProxSense® Series
Packaging and Pin-out
The IQS127D is available in a TSOT23-6 package.
Pin-out
IQS127D
TOUT 1
VSS 2
POUT 3
6 CX
5 VDDHI
4 VREG
Pin-out of IQS127D package
Pin-out description
IQS127D
Pin
Name
Type
Function
1
TOUT
Digital Out
Touch Output
2
VSS
Ground
GND Reference
3
POUT
Digital Out
Proximity Output
4
VREG
Analogue Output
Internal Regulator Pin
5
VDDHI
Supply Input
Supply Voltage Input
6
CX
Analogue I/O
Sense Antenna
Typical application schematic of
IQS127D.
Schematic
IQS127D
Typical values
DC Supply Input
Sense Antenna
VDDHI
CX
Rcx
CVDDHI
Touch Output Pin
TOUT
Proximity Output Pin
CV DDHI is optional for
added IC stability
POUT
VSS
VREG
Value
CVREG
1uF
RCX
470 Ω (typical)
CVDDHI
1uF
Keep track as
short as possible
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
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
Component
C VREG
GND
IQS127D Datasheet
Revision 1.16
Page 4 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
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.
configuration may be limited by values of external components chosen.
In-circuit
A number of standard device configurations are available (refer to Table 10.1). Azoteq can supply
pre-configured devices for large quantities.
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.
User Selectable Configuration Options: Bank 0
TTHR1
TTHR0
PTHR1
PTHR0
FUNC1
bit 7
FUNC0
LOGIC
~
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
Copyright © Azoteq (Pty) Ltd 2019.
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IQS127D Datasheet
Revision 1.16
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January 2023
Azoteq
IQ Switch®
ProxSense® Series
User Selectable Configuration Options: Bank 1
STREAMING
-
SHORT
STREAMING
tHALT1
tHALT0
bit 7
PMODE1
PMODE0
TTHR2
bit 0
Bank 1: bit 7
STREAMING: 1-wire streaming mode
0 = disabled
1 = enabled
-Section 7
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
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
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
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January 2023
Azoteq
IQ Switch®
ProxSense® Series
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 0). 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
t
t
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.
SAMPLE
CHARGE
Cx pin
1
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.
>
Note:
Refer to section 0 for the sourcing and sinking
capabilities of OUT, POUT and TOUT. These
pins are sourced from VDDHI and will be turned
>
HIGH=Logical ‘1’ and LOW=Logical ‘0’.
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
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
Revision 1.16
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January 2023
Azoteq
IQ Switch®
ProxSense® Series
HIGH (when active high) for a minimum time of
tHIGH, and LOW for a minimum time of tLOW (when
active low).
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 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
Output function: Active
Configuration: Bank0 bit1
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.
LOGIC: Output logic select Bit
Selection
0
Active Low
1
Active High
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
Active Mode Output Configuration
Output function: Latch (for tLATCH)
With a Proximity or Touch event, the output pin
will latch LOW for tLATCH seconds.
When the event terminates prior to tLATCH the
output pin will remain LOW.
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).
User Actuation
1
0
Output Pin
tLATCH
t LATCH
t LATCH
+ time that User Actuation stays active
1
0
Latch Mode Output Configuration
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
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January 2023
Azoteq
IQ Switch®
ProxSense® Series
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).
Output function: Toggle
The touch output pin will toggle with every
Touch event occurring. Thus when an event
User Actuation
1
0
Output Pin
1
0
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
The touch event is triggered based on TTH, CS
and LTA. A touch event is identified when for 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 bit0
PTHR1:PTHR0 Proximity Thresholds
Bit
Selection
00
2 (Most sensitive)
01
4
10
8
11
16 (Least sensitive)
TTHR2:TTHR0: Touch Thresholds
A proximity event is identified when for at least
6 consecutive samples the following equation
holds:
PTHR =< LTA-CS
Where LTA is the Long Term Average (refer to 6.6.1)
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)
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)
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
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January 2023
Azoteq
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
TOUCH threshold measured as Fraction of Current Sample:
I
F
G
H
J
K
E
1/32
1/16
2/16
3/16 4/16
6/16
Default Touch threshold = 1/16
8/16
Least
Sensitive
L
10/16
Proximity and Touch Thresholds.
Power Modes
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
whenever a current sample (CS) indicates a
Charge Cycle
Duration = tCHARGE
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
Zoom to Boost Mode after proximity detected
CX
tSAMPLE
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.
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
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
especially to detect 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
IQS127D Datasheet
Revision 1.16
Page 10 of 25
January 2023
IQ Switch®
ProxSense® Series
compensation only for environmental changes.
However there may be instances where sudden
changes in the environment or 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
>
1-Wire Data Streaming Mode
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 1-wire 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:
STREAMING: 1-wire data streaming mode
Bit
Selection
0
Disabled
1
Enabled
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.
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.
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
In order to compensate for noise the IQS127D
uses an IIR filter on the raw data to minimize
result of noise in the current sample. This filter
cannot be disabled.
Configuration: Bank1 bit7
Notes:
>
Azoteq
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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Azoteq
IQ Switch®
ProxSense® Series
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
t DATA
D6
D5
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.
D4
D3
D2
D1
D0
tSTOP
Stop – Start
Start
Stop – Start
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.
Byte Definitions for Short Data
Streaming Mode
Byte
Bit
Value
0
7:0
Current sample High byte
1
15:8
Current sample Low byte
2
23:16
LTA High byte
3
31:24
LTA Low byte
4
39
Proximity event detected
Touch event detected
Not used (always 0)
Zoom active
Non-user data
35:32
Byte Definitions for Normal Data
Streaming Mode
Byte
Bit
Value
0
7:0
CS High byte
1
15:8
CS Low byte
2
23:16
LTA High byte
3
31:24
LTA Low byte
4
39
38
37
36
35
34
33
32
ATI busy
Compensation (P5)
PTH0 – Proximity threshold
PTH1 – Proximity threshold
Not used (always 0)
Zoom active
Touch event detected
Proximity event detected
5
47
46
45
44
43
42
41
40
ATI Multiplier (I)
ATI Multiplier (S)
ATI Multiplier (S)
Compensation (P4)
Compensation (P3)
Compensation (P2)
Compensation (P1)
Compensation (P0)
6
55:48
Non-user data
7
63:56
Counter
Azoteq provides an application tool (GUI) that
can be utilised to capture and visualise the data
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
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IQ Switch®
ProxSense® Series
Azoteq
streamed from the IQS127D. Refer to the
Azoteq website for more details.
current samples are not within a predetermined
range.
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
instantaneous measurement and Prox/Touch
events are needed.
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.
Sample code available: “AZD017 - IQS127D 1Wire Protocol SAMPLE CODE”
Antenna
(ATI)
Tuning
Implementation
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.
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
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
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:
>
>
>
>
>
>
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).
IQS127D Datasheet
Revision 1.16
Page 13 of 25
January 2023
IQ Switch®
ProxSense® Series
>
>
>
Azoteq
Effective digital signal processing to remove
AC and other noise.
The very stable core of the devices.
The built in capability to accommodate a
large
range
of
sensing
antenna
capacitances.
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 100pF capacitor can be placed in parallel
with the 1uF capacitor between VDDHI and
VSS. Another 100pF 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
Revision 1.16
Page 14 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Electrical Specifications
Absolute Maximum Specifications
Exceeding these maximum specifications may cause damage to the device.
Operating temperature
-40°C to 85°C
Supply Voltage (VDDHI – VSS)
5.5V
Maximum pin voltage (OUT, TOUT, POUT)
VDDHI + 0.5V
Pin voltage (Cx)
2.5V
Minimum pin voltage (VDDHI, VREG, OUT, TOUT, POUT, Cx)
VSS - 0.5V
Minimum power-on slope
100V/s
HBM ESD
protection1
(VDDHI, VREG, VSS, TOUT/OUT, POUT/SHLD, Cx)
2kV
General Characteristics (Measured at 25°C)
IQS127D General Operating Conditions
DESCRIPTION
Conditions
Supply voltage
PARAMETER
MIN
VDDHI
2.95
2.35
TYP
MAX
UNIT
5.50
V
2.50
2.65
V
Internal regulator output
2.95 ≤ VDDHI ≤ 5.0
VREG
Boost operating current
2.95 ≤ VDDHI ≤ 5.0
IIQS127D BP
60
77
μA
Normal operating current
2.95 ≤ VDDHI ≤ 5.0
IIQS127D NP
23
29
μA
Low power operating current
2.95 ≤ VDDHI ≤ 5.0
IIQS127D LP1
17
22
μA
Low power operating current
2.95 ≤ VDDHI ≤ 5.0
IIQS127D LP2
13
17
μA
Start-up and shut-down slope Characteristics
1
DESCRIPTION
Conditions
PARAMETER
MIN
MAX
UNIT
POR
VDDHI Slope ≥ 100V/s
POR
1.45
1.70
V
BOD
VDDHI Slope ≥ 100V/s
BOD
1.30
1.40
V
VDDHIsafe reset
DC-level (not transient slope
dependent)
RESET ensure
0.6
V
See Section 9.4.1 for further details
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 15 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Output Characteristics (Measured at 25°C)
TOUT Characteristics
Symbol
Description
VOH
Output High
voltage
Symbol
Description
VOL
Output Low
voltage
ISOURCE (mA)
Conditions
MIN
TYP
1
VDDHI = 5V
4.5
1
VDDHI = 3.3V
2.97
1
VDDHI = 2.5V
2.25
ISINK (mA)
Conditions
MIN
TYP
1
VDDHI = 5V
0.30
0.50
1
VDDHI = 3.3V
0.20
0.33
1
VDDHI = 2.5V
0.20
0.25
MAX
UNIT
V
MAX
UNIT
V
POUT Characteristics
Symbol
Description
VOH
Output High
voltage
Symbol
Description
VOL
Output Low
voltage
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
ISOURCE (mA)
Conditions
MIN
5.0
VDDHI = 5V
4.5
2.5
VDDHI = 3.3V
2.97
2.5
VDDHI = 2.5V
2.25
ISINK (mA)
Conditions
MIN
TYP
3.0
VDDHI = 5V
0.1
0.5
2.5
VDDHI = 3.3V
0.1
0.33
2.5
VDDHI = 2.5V
0.1
0.25
IQS127D Datasheet
Revision 1.16
TYP
MAX
UNIT
V
MAX
UNIT
V
Page 16 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Electromagnetic Compatibility
Electrostatic discharge (ESD)
ESD Characteristics
Symbol
Ratings
Conditions
Level/
Class
Maximum
Value
UNIT
VESD(HBM)
Electrostatic discharge voltage
(Human body model)
TA = +25°C, conforming to
JESD22-A114
2
2000
V
VESD(CDM)
Electrostatic discharge voltage
(Charge device model)
TA = +25°C, conforming to
JESD22-C101-D
IV
1000
V
VESD(Product)
Electrostatic discharge voltage
(Product specification)2
TA = +25°C, conforming to
IEC61000-4-2, Airdischarge on all pins
4
±8
kv
VESD(Product)
Electrostatic discharge voltage
(Product specification)1
TA = +25°C, conforming to
IEC61000-4-2, Contactdischarge on all pins
3
±6
kv
Static Latch-Up (LU)
Static Latch-Up (LU)
Class
Symbol
Parameter
Conditions
A
LU
Static latch-up class
TA = +25°C, conforming to
EIA/JESD 78 IC latch-up
standard
For further details on test results please request from Azoteq.
2
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.
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 17 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Timing Characteristics
Main Oscillator NP mode3
SYMBOL
DESCRIPTION
Conditions
MIN
TYP
MAX
UNIT
FOSC
IQS127D Main oscillator
2.95 ≤ VDDHI ≤ 5.0
0.9
1
1.1
MHz
MAX
UNIT
General Timing Characteristics for 2.95V ≤ VDDHI ≤ 5.0V
SYMBOL
DESCRIPTION
Conditions
MIN
tHIGH
Output high minimum time
9
tLOW
Output low minimum time
9
TYP
ms
ms
FCX
Charge transfer frequency
1254
tLATCH
OUT high time in latch mode
(active high)
4.6
sec
tCHARGE
Charge cycle duration
7.2
ms
tSAMPLE
Refer to section 5
tBP
Sampling period in BP
tCHARGE - 2 ≤ tSAMPLE
9
ms
tBP
Sampling period in BP
tCHARGE ≥ tSAMPLE
tCHARGE+2
ms
tSTART
Refer to section 7
tINIT
Refer to section 7
136
us
tDATA
Refer to section 7
136
us
tNP
Sampling period in NP
50
ms
tLP1
Sampling period in LP1
100
ms
tLP2
Sampling period in LP2
200
ms
tZOOM
Period in BP after possible
event
4.6
s
CS = 900
ms
14.4
17
3
All timings are derived from the main oscillator.
4
IQS127DP is screened to prevent any charge transfers between 126.8kHz and 130.3kHz.
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
kHz
IQS127D Datasheet
Revision 1.16
18.8
us
Page 18 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
IQS127D Response Times
Proximity
Power Mode
IC Batch #
Min
Max
Unit
Boost Power
54
63
ms
All
Normal Power
95
145
ms
All
Low Power 1
145
245
ms
All
Low Power 2
245
445
ms
All
Touch
Power Mode
IC Batch #
Typical
Unit
All
250
ms
Up to 127DBD
All
120
ms
From 127DBx
Packaging Information
TSOT23-6
C
A
B
D
E
F
G
J
I
H
TSOT23-6 Packaging5
5
Drawing not on Scale
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 19 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
TSOT23-6 Dimensions
Dimension
Typical
Tolerance
A
2.80 mm
Basic
B
1.60 mm
Basic
C
2.90 mm
Basic
D
0.40 mm
±0.10mm
E
0.95 mm
Basic
F
1.00mm
Max
G
0.05 mm
±0.05mm
H
0.40 mm
±0.10mm
I
4
±4°
J
0.127 mm
+0.07/-0.007
TSOT23-6 Tape
IQS127D Tape Specification
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 20 of 25
January 2023
IQ Switch®
ProxSense® Series
Azoteq
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
Level (duration)
TSOT23-6
MSL 1 ( Unlimited at ≤30 °C/85% RH)
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 21 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Datasheet and Part-number Information
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
IC NAME
BULK PACAKAGING
CONFIGURATION
PACKAGE TYPE
IC NAME
IQS127D
IQS127DP
=
=
IQS127 with Dual outputs
IQS127 with Dual outputs, Charge Frequency offset
CONFIGURATION
zzzzz
=
IC Configuration (hexadecimal)
PACKAGE TYPE
TS
=
TSOT23-6
=
Reel (3000pcs/reel) – MOQ = 3000pcs
BULK PACKAGING R
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 Devices Available
6
Standard Devices6
Function
IQS127D-00000TSR
Default
IQS127D-00002TSR
Active HIGH outputs
IQS127D-00200TSR
Normal Power Mode
IQS127D-00008TSR
Touch Output ac Toggle
All configurations ‘default’ except those mentioned under Function
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 22 of 25
January 2023
Azoteq
IQ Switch®
ProxSense® Series
Device Packaging Convention
Top
127y xx
IC NAME
IC Name
BATCH
BATCH
127D
XX
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
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 23 of 25
January 2023
IQ Switch®
ProxSense® Series
Azoteq
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 0
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
Version 1.16
Add 127DP version information (charge frequency offset)
Copyright © Azoteq (Pty) Ltd 2019.
All Rights Reserved.
IQS127D Datasheet
Revision 1.16
Page 24 of 25
January 2023
IQ Switch®
ProxSense® Series
Azoteq
Contact Information
USA
Asia
South Africa
Physical
Address
11940 Jollyville
Suite 120-S
Austin
TX 78759
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 78759
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 information 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 or caused by, without limitation, failure of performance, error,
omission, interruption, defect, delay in operation or transmission, 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 or 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 prior 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.
IQS127D Datasheet
Revision 1.16
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Page 25 of 25
January 2023
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