ETC2 IQS156 Iq switch - proxsense sery Datasheet

IQ Switch®
ProxSense® Series
IQS156 Datasheet
IQ Switch® - ProxSense® Series
Minimalist Capacitive Sensor with Compensation for Sensitivity Reducing Objects
Unparalleled Features
Sub 6uA current consumption
Automatic tuning for optimal operation in various environments
The IQS156 ProxSense® IC is a fully integrated six channel capacitive contact and proximity
sensor with market leading sensitivity and automatic tuning to the sense electrodes. The IQS156
provides a minimalist implementation requiring as few as 2 external components. The device is
ready for use in a large range of applications while programming options allow customisation for
specialized applications.
Main Features
6 Channel input device
I2C data output
ATI: Automatic tuning to optimum sensitivity
Supply Voltage 3V to 5.5V
8 Power Modes (6µA min)
Internal voltage regulator and reference capacitor
Large proximity detection range
IQS143 MSOP10
Representations only, not
actual markings
Automatic drift compensation
Development and Programming tools available (VisualProxSense and USBProg)
Small outline MSOP–10
Applications
White goods and appliances
Office equipment, toys, sanitary ware
Flame proof, hazardous environment Human Interface Devices
Proximity detection that enables backlighting activation (Azoteq Patented)
Wake-up from standby applications
Replacement for electromechanical switches
GUI trigger on proximity detection.
Available options
TA
MSOP-10
IQS156
-40°C to 85°C
IQ Switch®
ProxSense® Series
Table 1.1
Functional Overview
1 Introduction
The IQS156 is a six channel projected
capacitive proximity and touch sensor
featuring internal voltage regulator and
reference capacitor (Cs).
The device has five dedicated input pins for
the connection of the sense electrodes, which
comprises of three receivers, and two
transmitters. Two output pins are used for
serial data communication through the I2C
protocol.
The devices automatically tracks slow varying
environmental changes via various filters,
detect noise and has an automatic Automatic
Tuning Implementation (ATI) to tune the
device for optimal sensitivity.
1.1 Applicability
All specifications, except where specifically
mentioned otherwise, provided by this
datasheet are applicable to the following
ranges:
Temperature -40°C to +85°C
Supply voltage (VDDHI) 3V to 5.5V
1.2 Pin-outs
Pin
I2C
Function
1
GND
Ground
4
VDDHI
Power
Input
5
VREG
Regulator
Pin
2
CRX0
Receiver
Electrode
3
CRX1
Receiver
Electrode
9
CRX2
Receiver
Electrode
10
CTX0
Transmitter
Electrode
6
CTX1
Transmitter
Electrode
7
SDA
I2C Data
8
SCL
I2C Clock
2 Analogue Functionality
1. GND
10. CTX0
2. CRX0
9. CRX2
3. CRX1
8. SCL
4. VDDHI
7. SDA
5. VREG
6. CTX1
Figure 1.1
IQS156 Pin-outs.
IQS156 Pin-outs.
The analogue circuitry measures the
capacitance of the sense electrodes attached
to the Cx pins through a charge transfer
process that is periodically initiated by the
digital circuitry. The measuring process is
referred to a conversion and consists of the
discharging of Cs 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 Count
Values (CS).
The capacitance measurement circuitry
makes use of an internal Cs and voltage
reference (VREG).
The analogue
functionality for:
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IQS156 Datasheet
Revision 1.7
circuitry
further
provides
Page 2 of 24
October 2012
IQ Switch®
ProxSense® Series
Power on reset (POR) detection.
Brown out detection (BOD).
3 Digital Functionality
The digital processing
responsible for:
functionality
is
Monitoring and automatic execution of the
ATI algorithm.
Signal processing and digital filtering.
Detection of PROX and TOUCH events.
Managing outputs of the device.
Managing serial communications.
Management of BOD and WDT events.
Initiation of conversions at the selected
rate.
Processing of CS and execution of
algorithms.
Detailed Description
4 Reference Design
Figure 4.1
Reference Design.
Use C3 and C4 for added RF immunity.
Place C1-C4 as close as possible to IC, connected to good GND.
R6 and R7 used as pull up resistors for I2C protocol.
Figure 4.2
Output in active low.
5 High Sensitivity
Through patented design and advanced signal
processing, the device is able to provide
extremely high sensitivity to detect Proximity.
This enables designs that can detect
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proximities at distances that cannot be
equalled by most other products. When the
device is used in environments where noise or
ground effects exist that lower the sensitivity,
a reduced proximity threshold is proposed to
ensure reliable functioning of the sensor. The
high sensitivity allows the device to sense
IQS156 Datasheet
Revision 1.7
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October 2012
IQ Switch®
ProxSense® Series
accurately through overlays with low dielectric
constants like wood or even air gaps.
8 Charge Transfers
The IQS156 charges in 7 timeslots, with one
internal Cs capacitor. The charge sequence is
6 Adjustable Proximity
shown in Figure 8.1, where CH0 is the Prox
Threshold
channel, and charges before each of the 6
The IQS156 has a default proximity threshold of input channels.
4. The proximity threshold is selected by the
CH0
CH1 0 CH2 0 CH3 0 CH4 0 CH5 0 CH6 0
PROX
designer (1 to 64) to obtain the desired
sensitivity and noise immunity through the I2C
CH1+
CTX0
CTX0
CTX0
CTX1
CTX1
CTX1
CH2+
CRX0
CRX1
CRX2
CRX0
CRX1
CRX2
serial interface. The proximity event is triggered
CH3
based on the selected proximity threshold; the
CS, LTA (Long Term Average) and LTN (Long
Figure 8.1 IQS156 Charge transfer.
Term Noise) filter. The threshold is expressed in
terms of counts; the same as CS.
9 Data Streaming
A proximity event is identified when for at least
4 consecutive samples the following equation The IQS156 device interfaces to a master
controller via a 2 wire serial interface bus that is
holds:
I2CTM compatible.
PTH =< LTA-CS
The IQS156 can only function as a slave
Where LTA is the Long Term Average
device on the bus. The bus must be controlled
by a master device which generates the serial
7 Adjustable Touch
clock (SCL), controls bus access, and
generates the START and STOP conditions.
Thresholds
The IQS156 has a default touch threshold of
96 (for all six channels). The touch threshold
is selected by the designer to obtain the
desired touch sensitivity and is selectable in
the memory map, individually for each
channel.
The touch event is triggered based on TTH, CS
and LTA. A touch event is identified when for
at least 4 consecutive samples the following
equation holds:
TTH =< LTA-CS
The serial clock (SCL) and serial data lines
(SDA) are open-drain and therefore must be
pulled high to the operating voltage with a pullup resistor (typically 10k).
9.1 Bus Characteristics
The following bus protocol has been defined:
Data transfer may only be initiated 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 is HIGH will be interpreted as START
and STOP conditions.
With lower average CS (therefore lower LTA)
values the touch threshold will be lower and
vice versa.
The following conditions have been defined for
the bus (refer to Figure 9.1):
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IQS156 Datasheet
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IQ Switch®
ProxSense® Series
SCL
(A)
(B)
(D)
(D)
(C)
(A)
SDA
Address or
Acknowledge
Valid
Start Condition
Figure 9.1
Data Allowed
to Change
Stop Condition
Data Transfer Sequence on the Serial Bus.
9.1.2 Bus Idle (A)
The SCL and SDA lines are both HIGH.
9.1.3 START Condition (B)
The IQS156 does not generate any
acknowledge bits while it is not in its
communication window.
9.2 Acknowledge Polling
A start condition is implemented as a HIGH to
LOW transition of SDA, while the SCL is The IQS156 does not have a RDY pin, thus
HIGH. All serial communication must be ACK polling must be used to determine when
the device is ready for communication. The
preceded by a START condition.
device will not acknowledge during a
9.1.4 STOP Condition (C)
conversion cycle.
A stop condition is implemented as a LOW to Once a stop condition is sent by the master
HIGH transition of SDA, while the SCL is the device will perform the next conversion
HIGH. All serial communication must be cycle. ACK polling can be initiated at any time
ended by a STOP condition. NOTE: When a during the conversion cycle to determine if the
STOP condition is sent, the device will exit the device has entered its communication window.
communications window and continue with
To perform ACK polling the master sends a
conversions.
start condition followed by the control byte. If
9.1.5 Data Valid (D)
the device is still busy then no ACK will be
The state of the SDA line represents valid returned. If the device has completed its cycle
data when, after a START condition, the SDA the device will return an ACK, and the master
is stable for the duration of the HIGH period of can proceed with the next read or write
operation (refer to Figure 9.2).
the clock signal.
The data on the line must be changed during
the LOW period of the clock signal. There is
one clock pulse per bit of data.
Each data transfer is initiated with a START
condition and terminated with a STOP
condition.
9.1.6 Acknowledge
The slave device must acknowledge (ACK)
after the reception of each byte. The master
device must generate an extra (9th) clock
pulse which is associated with this
acknowledge
bit.
The
device
that
acknowledges, has to pull down the SDA line
during the acknowledge clock pulse. NOTE:
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IQS156 Datasheet
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IQ Switch®
ProxSense® Series
Send
Start
__
R/W
Slave Address (7 Bit)
Send Control
Byte
LSB
MSB
No
Figure 9.3
Control Byte Format.
9.4 Sub addressing
Did Device
Acknowledge?
Each slave device on the serial bus requires a
unique 7 bit device identifier. When the control
byte is sent by the master the device will be
able to determine if it is the intended recipient
of a data transaction. The IQS156 address
selection is controlled with OTP fuse selection.
Four addresses are available, and can be
programmed by USBProg.
Yes
Continue
with I2C
Operation
Figure 9.2
ACK Polling.
Table 9.1
9.3 Control Byte Format
A control byte is the first byte received
following the start condition from the master
device. The control byte consists of a 7 bit
device address and the Read/ Write indicator
bit (refer to Figure 9.3).
I2C Sub Addresses.
SA1
SA0
Address
(7-bit)
0
0
0x40
0
1
0x41
1
0
0x42
1
1
0x43
9.5 Memory Mapping
Address
Size(Bytes)
00h-0Fh
16
R/W
Device Information
R
10h-30h
32
R/W
Device Specific Data
R
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IQS156 Datasheet
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IQ Switch®
ProxSense® Series
31h-34h
35h-38h
39h-3Ch
3Dh-41h
42h-82h
4
4
4
4
Proximity Status Bytes
Touch Status Bytes
Halt Bytes
Active Bytes (indicate cycle)
64
R/W
R
R/W
R
R/W
R
R/W
R
R/W
Counts
R
83h-C3h
64
R/W
LTAs
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IQS156 Datasheet
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IQ Switch®
ProxSense® Series
R
C4h-FDh
64
R/W
Device Settings
W
9.5.1 Device Information
00H
Product Number
Bit
7
6
5
01H
Bit
7
6
5
4
3
R/W
2
1
0
11 H
R
Version Number
R/W
4
3
2
1
0
10 H
R
Prox Status Bits
R/W
9.5.2 Device Specific Data
10H
Bit
7
6
5
4
3
2
1
0
System
use
System
use
System
use
NP
Segment
Active
Low
Power
Active
ATI
Busy
RF
Noise
Zoom
9.5.3 Proximity Status Bytes
The proximity status of all the channels on the device are shown here.
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R
IQ Switch®
ProxSense® Series
31H
Proximity 0 (CH0)
Bit
7
6
5
4
R/W
3
2
1
SHOW_RESET
0
CH0
R
9.5.4 Touch Status Bytes
The touch status of all the channels on the device are shown here.
35H
Touch 0 (CH1-CH6)
Bit
7
R/W
6
5
4
3
2
1
CH6
CH5
CH4
CH3
CH2
CH1
0
R
9.5.5 Halt Bytes
The filter halt status of all the channels on the device are shown here.
39H
Halt 0 (CH0-CH6)
Bit
7
R/W
6
5
4
3
2
1
0
CH6
CH5
CH4
CH3
CH2
CH1
CH0
R
Channel Number (indicate cycle the channel number that the data in this cycles represents)
3DH
CHAN_NUM
Bit
7
6
5
4
3
R/W
2
1
0
R
9.5.6 Counts
The values that are available here are only the transfers from the current cycle.
42H
Count
Bit
7
6
5
4
7
6
5
3
2
1
0
HIGH byte
R
Count
R/W
43H
Bit
R/W
4
3
2
1
0
LOW byte
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IQS156 Datasheet
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IQ Switch®
ProxSense® Series
9.5.7 Long-Term Averages
The values that are available here are only the transfers from the current cycle.
83H
Long-Term Average
Bit
7
6
5
84H
Bit
7
6
5
4
3
R/W
2
1
0
HIGH byte
R
Long-Term Average
R/W
4
3
2
1
0
LOW byte
R
9.5.8 Device Settings
It is attempted that the common used settings are situated closer to the top of the memory
block. Settings that are regarded as more „once-off‟ are placed further down.
C4H
Channel 0 Compensation Setting
Bit
7
6
5
4
3
2
R/W
1
0
Compensation 0 <5:0>
Comp5:Comp0
R/W
Sets the compensation value for channel 0
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
C5H
Channel 1 Compensation Setting
Bit
7
6
5
4
3
Compensation 1 <5:0>
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IQS156 Datasheet
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2
R/W
1
0
R/W
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IQ Switch®
ProxSense® Series
Comp5:Comp0
Sets the compensation value for channel 1
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
C6H
Channel 2 Compensation Setting
Bit
7
6
5
4
3
2
R/W
1
0
Compensation 2 <5:0>
Comp5:Comp0
R/W
Sets the compensation value for channel 2
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
C7H
Channel 3 Compensation Setting
Bit
7
6
5
4
3
2
R/W
1
0
Compensation 3 <5:0>
Comp5:Comp0
R/W
Sets the compensation value for channel 3
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
C8H
Channel 4 Compensation Setting
Bit
7
6
5
4
3
Compensation 4 <5:0>
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IQS156 Datasheet
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2
R/W
1
0
R/W
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IQ Switch®
ProxSense® Series
Comp5:Comp0
Sets the compensation value for channel 4
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
C9H
Channel 5 Compensation Setting
Bit
7
6
5
4
3
2
R/W
1
0
Compensation 5 <5:0>
Comp5:Comp0
R/W
Sets the compensation value for channel 5
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
CAH
Channel 6 Compensation Setting
Bit
7
6
5
4
3
2
R/W
1
0
Compensation 6 <5:0>
Comp5:Comp0
R/W
Sets the compensation value for channel 6
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
CBH
Channel 0 Multiplier Setting
Bit
7
6
5
4
3
Multiplier 0 <4:0>
R/W
2
1
0
R/W
Multiplier Settings registers sets the Multiplier values for each channel, which determines the
sensitivity, and compensation to reach ATI routine target.
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IQ Switch®
ProxSense® Series
Mul4:Mul3
Sensitivity Multiplier
Mul2:0
Compensation Multiplier
Can set the counts outside the ATI routine limit if “ATI OFF” is
not set. This event will trigger re-ATI.
CCH
CH1 Touch Threshold
Bit
7
6
5
TTH2
TTH1
TTH0
CDH
4
3
R/W
2
1
0
Multiplier 1 <4:0>
R/W
CH2 Touch Threshold
Bit
7
6
5
TTH2
TTH1
TTH0
CEH
4
3
R/W
2
1
0
Multiplier 2 <4:0>
R/W
CH3 Touch Threshold
Bit
7
6
5
TTH2
TTH1
TTH0
CFH
4
3
R/W
2
1
0
Multiplier 3 <4:0>
R/W
CH4 Touch Threshold
Bit
7
6
5
TTH2
TTH1
TTH0
D0H
4
3
R/W
2
1
0
Multiplier 4 <4:0>
R/W
CH5 Touch Threshold
Bit
7
6
5
TTH2
TTH1
TTH0
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4
3
R/W
2
Multiplier 5 <4:0>
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0
R/W
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IQ Switch®
ProxSense® Series
D1H
CH6 Touch Threshold
Bit
7
6
5
4
TTH2
TTH1
TTH0
3
R/W
2
0
Multiplier 6 <4:0>
Bits
Selection
(TTH_Range = 0)
Selection
(TTH_Range = 1)
000
96
24
001
32
8
010
64
16
011
128
32
100
196
48
101
256
64
110
384
96
111
512
128
D2H
1
R/W
Proximity Sensitivity Settings (PROX_TH_CH0)
Bit
7
6
R/W
5
4
3
2
1
0
PT_5
PT_4
PT_3
PT_2
PT_1
PT_0
R/W
Custom value between 1 and 63 can be set with bit 5:0 to implement the Proximity Threshold.
The default Prox Threshold of the IQS156 is 4.
Touch Treshold Range Selection Bits – CH1-CH6 (TTH_RANGE)
D3H
Bit
Default
7
6
5
4
3
2
1
CH6
Low
Range
CH5
Low
Range
CH4
Low
Range
CH3
Low
Range
CH2
Low
Range
CH1
Low
Range
0
0
0
0
0
0
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IQS156 Datasheet
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R/W
0
R/W
Page 14 of 24
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IQ Switch®
ProxSense® Series
CH7 low
Range:CH0
low Range
D4H
Select the low or normal range for Touch Thresholds:
„0‟: Low Range
„1‟: Normal Range
ProxSense Module Settings 0 (PROX_SETTINGS0)
Bit
7
6
5
ATI
OFF
Partial
ATI
ATI OFF
4
3
2
R/W
1
0
Base 1
Base 0
R/W
If this bit is set, the ATI routine will not be able to run:
„0‟: Disabled
„1‟: Enabled
Partial ATI
Disables the Base bits to set the base value for the Prox
Channel
“0”: Enabled
“1”: Disabled
Base1:Base0
Controls the base value for the ATI routine of the Prox channel,
if Partial ATI = 0:
„00‟: 200
„01‟:50
„10‟: 150
„11‟: 250
D5H
ProxSense Module Settings 1 (PROX_SETTINGS1)
Bit
7
6
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5
R/W
4
3
2
1
0
ND_
ND_
FORCE_
Redo_
Reseed
LEVEL
ON
HALT
ATI
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IQ Switch®
ProxSense® Series
ND Level
Selects the noise detect level
„0‟: 25mV
„1‟: 50mV
ND On
Enables the noise detection.
„0‟: Disabled
„1‟: Enabled
Force Halt
Forces the Long Term Average to stop being calculated
„0‟: LTA updates normally
„1‟: LTA is halted
Redo ATI
Forces the ATI routine to run when a „1‟ is written into this bit
position. ATI OFF in D4 should not be set.
Reseed
All channels are reseeded when a „1‟ is written into this bit
position. The LTA‟s are set to 8 counts above the counts.
D6H
ProxSense Module Settings 2 (PROX_SETTINGS2)
Bit
R/W
7
6
5
4
3
2
1
0
Ack
WDT
Sync
Halt1
Halt0
LP2
LP1
LP0
Reset
Off
On
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IQ Switch®
ProxSense® Series
Ack Reset
Clears the “RESET” indication flag
WDT Off
Sets the watchdog timer:
0 = Enabled
1 = Disabled
Sync On
Sync on Data line
0 = OFF
1 = ON (IQS156 will pulse the SDA line low when comms
window is open)
Halt1:Halt0
Sets the Halt time for the LTA (time before recalibration):
00 = 20 Seconds
01 = 40 Seconds
10 = Never
11 = Permanent
LP2:LP0
Controls the charge cycle time:
000 = 9ms
001 = 128ms
010 = 256ms
011 = 384ms
100 = 512ms
101 = 768ms
110 = 1s
111 = 2s
Channel Enable for CH0 – CH6 (CHAN_ACTIVE)
D7H
Bit
7
R/W
6
5
4
3
2
1
0
CH6
CH5
CH4
CH3
CH2
CH1
CH0
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IQ Switch®
ProxSense® Series
CH6:CH0
Software enable or disable of channels:
0 = Channel Disabled
1 = Channel Enabled
D8H
DEFAULT_COMMS_POINTER
Bit
7
6
Default
5
4
3
2
R/W
1
0
10H (beginning of Device Specific Data)
FCH
R/W
Direct Address R/W
Bit
7
6
5
7
3
2
1
0
Address location to perform Direct Read/Write
R/W
Direct Data R/W
R/W
FDH
Bit
4
R/W
6
5
4
3
Data to Read/Write
10 Auto 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 - Auto Tuning Implementation).
2
1
0
R/W
The adjustment of the ATI parameters will
result in variations in the count and sensitivity.
Sensitivity can be observed as the change in
count 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
count. The sensitivity of the various options
may however be different for the same count.
ATI makes adjustments through external
reference capacitors (as required by most
10.1 Automatic ATI
other
solutions)
to
obtain
optimum
The IQS156 implements an automatic ATI
performance.
algorithm. This algorithm automatically adjusts
ATI adjusts internal circuitry according to two
the ATI parameters to optimise the sensing
parameters, the ATI multiplier and the ATI
electrodes‟ connection to the device.
compensation. The ATI multiplier can be
viewed as a course adjustment and the ATI The device will execute the ATI algorithm
whenever the device starts-up and when the
compensation as a fine adjustment.
counts are not within a predetermined range.
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
IQS156 Datasheet
Revision 1.7
Page 18 of 24
October 2012
IQ Switch®
ProxSense® Series
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 count has been detected.
The automatic ATI function aims to maintain a
constant count, regardless of the capacitance
of the sense electrode (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 electrode
at start-up to optimise the sensitivity of
the application.
Automatic re-tuning when the device
detects changes in the sensing
electrodes‟ capacitance to accommodate
a large range of changes in the
environment of the application that
influences the sensing electrodes.
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 influences the
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
normal functioning of the device, but in
most instances the effect will be hardly
noticeable.
Shortly after the completion of the retuning process the sensitivity of Proximity
detection may be reduced slightly for a
few seconds as internal filters stabilises.
Automatic ATI can be implemented so
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.
The built in capability to accommodate a
large range of sensing electrode
capacitances.
10.2 Partial ATI
By default (Address: D4H bit 5 = 0) the ATI
routine sets the required base value of the
touch channels to 250 counts The required
base value for the proximity channel is
specified through I2C commands in address
D3H bits [1:0] and is default 200.
Alternatively (Address: D4H bit 5 = 1), the
user can set the multiplier bits through
address CBH through D1H bits [5:0] and this
would determine the sensitivity, and
compensation (scaled) to reach the ATI target.
With the base value set, the Partial ATI routine
would use a convergence technique with a
fixed amount of steps to reach its aimed value.
IQS156 Datasheet
Revision 1.7
Page 19 of 24
October 2012
IQ Switch®
ProxSense® Series
11 Specifications
11.1 Absolute Maximum Specifications
The following absolute maximum parameters are specified for the device:
Exceeding these maximum specifications may cause damage to the device.
Operating temperature
Supply Voltage (VDDHI – GND)
Maximum pin voltage
Maximum continuous current (for specific Pins)
Minimum pin voltage
Minimum power-on slope
ESD protection
Maximum pin temperature during soldering
Maximum body temperature during soldering
Table 11.1
-40°C to 85°C
5.5V
VDDHI + 0.5V
GND - 0.5V
100V/s
±3kV
IQS156 General Operating Conditions1
DESCRIPTION
Conditions
Supply voltage
PARAMETER
MIN
VDDHI
2.95
2.35
TYP
MAX
UNIT
5.50
V
2.65
V
Internal regulator output
2.95 ≤ VDDHI ≤ 5.0
VREG
Boost mode operating
current
3.3V
IIQS156 BP
230
μA
Normal operating current
3.3V
IIQS156 NP
17
μA
Low Power Operating
current
3.3V
IIQS156 LP1
11
μA
Low Power Operating
current
3.3V
IIQS156 LP2
9
μA
Low Power Operating
current
3.3V
IIQS156 LP3
8
μA
Low Power Operating
current
3.3V
IIQS156 LP4
7
μA
Low Power Operating
current
3.3V
IIQS156 lP5
6.5
μA
Low Power Operating
current
3.3V
IIQS156 lP6
<6
μA
1
2.50
Operating current figure shown here, do not include current flow through I2C pull up resistors.
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
IQS156 Datasheet
Revision 1.7
Page 20 of 24
October 2012
IQ Switch®
ProxSense® Series
Table 11.2
Start-up and shut-down slope Characteristics
DESCRIPTION
Conditions
PARAMETER
MIN
MAX
UNIT
POR
VDDHI Slope ≥ 100V/s
POR
0.92
2.3
V
BOD
1
1.54
V
BOD
Table 11.3
Initial Touch Times
DESCRIPTION
PARAMETER
MIN
MAX
Unit
BP1
Report Rate
117
223
ms
NP
Report Rate
126
252
ms
LP6
Report Rate
126
2124
ms
Table 11.4
Repetitive Touch Rates
DESCRIPTION
Conditions
PARAMETER
Sample
rate = 5ms
Sample
rate = 9ms
UNIT
All power modes
Zoom active
Response Rate2
>5
>2
Touches/second
The sample rate of the IQS156 is increased by:
Faster communication
Less data transfer
1
Communication and charge frequency to comply with sample rate as reported earlier in this datasheet.
2
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
Debounce of 3 (up and down)
IQS156 Datasheet
Revision 1.7
Page 21 of 24
October 2012
IQ Switch®
ProxSense® Series
12 Mechanical Dimensions
Figure 12.1 MSOP-10 Back view.
Figure 12.3 MSOP-10 Top view.
Figure 12.2 MSOP-10 Side view.
Figure 12.4 MSOP-10 Footprint.
Table 12.1 MSOP-10 Footprint
Dimensions from Figure 12.4.
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
Dimension
[mm]
Pitch
0.50
C
4.40
Y
1.45
X
0.30
IQS156 Datasheet
Revision 1.7
Page 22 of 24
October 2012
IQ Switch®
ProxSense® Series
13 Device Marking
IQS156 x t z PWWYY
REVISION
DATE CODE
SUB ADDRESS
CONFIGURATION
TEMPERATURE
REVISION
x
TEMPERATURE RANGE
t
=
=
I
=
IC CONFIGURATION
IC Revision Number
z
C
=
DATE CODE
-40°C to 85°C (Industrial)
0°C to 70°C (Commercial)
Configuration (Hexadecimal)
P
=
Package House
WW
=
Week
YY
=
Year
14 Ordering Information
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.
IQS156 z pp b
BULK PACKAGING
IC NAME
SUB ADDRESS
CONFIGURATION
PACKAGE TYPE
IC NAME
CONFIGURATION
IQS156
z
=
PACKAGE TYPE
BULK PACKAGING
R
IQS156
Sub Address Configuration (hexadecimal)
MS
=
T
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
=
=
MSOP-10
Reel (4000pcs/reel) – MOQ = 4000pcs
=
IQS156 Datasheet
Revision 1.7
Tube (96pcs/tube)
Page 23 of 24
October 2012
IQ Switch®
ProxSense® Series
15 Contact Information
PRETORIA OFFICE
PAARL OFFICE
Physical Address
Physical Address
160 Witch Hazel Avenue
109 Main Street
Hazel Court 1, 1st Floor
Paarl
Highveld Techno Park
7646
Centurion, Gauteng
Western Cape
Republic of South Africa
Republic of South Africa
Tel: +27 12 665 2880
Tel: +27 21 863 0033
Fax: +27 12 665 2883
Fax: +27 21 863 1512
Postal Address
Postal Address
PO Box 16767
PO Box 3534
Lyttelton
Paarl
0140
7620
Republic of South Africa
Republic of South Africa
The following patents relate to the device or usage of the device: US 6,249,089 B1, US 6,621,225 B2, US
6,650,066 B2, US 6,952,084 B2, US 6,984,900 B1, US 7,084,526 B2, US 7,084,531 B2, US 7,119,459 B2,
US 7,265,494 B2, US 7,291,940 B2, US 7,329,970 B2, US 7,336,037 B2, US 7,443,101 B2, US 7,466,040
B2, US 7,498,749 B2, US 7,528,508 B2, US 7,755,219 B2, US7,772,781, US 7,781,980 B2, EP 1 120 018
B1, EP 1 206 168 B1, EP 1 308 913 B1, EP 1 530 178 B1, ZL 99 8 14357.X, AUS 761094
IQ Switch®, ProxSense™, LightSense™, AirButton® and the IQ Logo are
trademarks of Azoteq.
The information appearing in this Datasheet is believed to be accurate at the time of
publication. However, Azoteq assumes no responsibility arising from the use of the
specifications described. 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 or otherwise, under any intellectual property rights. Azoteq
reserves the right to alter its products without prior notification. For the most up-to-date
information, please refer to www.azoteq.com.
WWW.AZOTEQ.COM
[email protected]
Copyright © Azoteq (Pty) Ltd 2012.
All Rights Reserved.
IQS156 Datasheet
Revision 1.7
Page 24 of 24
October 2012
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Azoteq:
IQS156MSR
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