GSL1688 - NewHaven Display

GSL1680, 1688 Capacitive Touchscreen Controller
Features
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Highlight
o Outstanding anti RF, LCD and power supply interference
o Perfect soft-touch feeling
o Auto tuning and auto calibration
Number of Channels
o Up to 16x10
o Detect up to 10 fingers
o Scan order programmable
Zero Additional part Count
o Power bypass capacitor only
Signal Processing
o Advanced anti-interference signal processing using both hardware engine and firmware
o Self-Calibration
o Water and face suppression
o Down and up scaling support to match LCD resolution
o Support axis flipping and axis switch over for portrait and landscape modes
Scan Speed
o Maximum single touch up to 200Hz
o Configurable to allow power/speed optimization
Response times
o Initial latency < 10ms for first touch from idle
Sensors
o Support single layer ITO true multi-touch mutual capacitive sensor
o Support non-MoAlMo sensor
o Support OGS ( one glass sensor)
o Works with PET or glass sensors, including curved profiles
o Works with single or dual ITO layer
o Works with all proprietary sensor patterns on the markets
o Works with passive stylus
Panel Thickness
o Glass up to 2.5mm, screen size dependent
o Plastic up to 1.2mm, screen size dependent
Interface
o I2C compatible slave mode 400KHz.
o Interrupt to Host
Power
o Single Power supply, 2.6v~3.3v
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
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o I/O Interface 1.8v /3.3 compatible
Power consumption
o Active: <9mA, subject to configuration
o Green: <3mA, subject to configuration
o Sleep: <30uA
Package
o 40-pin QFN, 5x5 mm
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
Contents
Features................................................................................................................................................................1
1.
2.
3.
4.
Pinout and Schematic .................................................................................................................................6
1.1.
Pinout Configuration ..........................................................................................................................6
1.2.
Pinout Description ..............................................................................................................................6
1.3.
Schematic ............................................................................................................................................8
Overview......................................................................................................................................................8
2.1.
Introduction ........................................................................................................................................8
2.2.
Resources ............................................................................................................................................9
Capacitive touch Basics.............................................................................................................................10
3.1.
Sensor and Electrode construction..................................................................................................10
3.2.
Scanning Sequence ...........................................................................................................................11
3.3.
Touchscreen sensitivity ....................................................................................................................11
Detail Operation........................................................................................................................................12
4.1.
Power Up and Reset .........................................................................................................................12
4.2.
Calibration .........................................................................................................................................12
4.3.
Communication.................................................................................................................................13
4.3.1.
Communications Protocol .......................................................................................................13
4.3.2.
I2C-compatible Addresses .......................................................................................................13
4.3.3.
Writing to the Device ...............................................................................................................13
4.3.4.
Reading from the Device..........................................................................................................14
4.3.5.
SDA, SCL.....................................................................................................................................14
4.3.6.
IRQ .............................................................................................................................................15
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
4.4.
Operation mode................................................................................................................................15
4.4.1.
Shutdown mode .......................................................................................................................15
4.4.2.
Running modes.........................................................................................................................15
4.5.
Circuit Component............................................................................................................................16
4.5.1.
Bypass Capacitors.....................................................................................................................16
4.5.2.
PCB Cleanliness.........................................................................................................................16
4.6.
5.
6.
7.
Signal processing...............................................................................................................................16
4.6.1.
Anti-EMI interference...............................................................................................................16
4.6.2.
Floating Terminal......................................................................................................................16
4.6.3.
Inter Finger Interference..........................................................................................................17
4.6.4.
Face and Water Suppression ...................................................................................................17
Getting Start with GSL168X......................................................................................................................17
5.1.
Connection with Host.......................................................................................................................17
5.2.
Configuring the Device .....................................................................................................................18
5.3.
Communications With the Host.......................................................................................................18
5.4.
Steps to Start GSL168X .....................................................................................................................18
Specification ..............................................................................................................................................19
6.1.
Operating Conditions........................................................................................................................19
6.2.
DC Specification ................................................................................................................................19
6.3.
I2C-compatible Bus Specifications...................................................................................................19
6.4.
Power Consumption .........................................................................................................................20
6.5.
Moisture Sensitivity Level ................................................................................................................20
Package ......................................................................................................................................................21
7.1.
Mechanic Dimention ........................................................................................................................21
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
7.2.
Marking..............................................................................................................................................22
7.3.
Part Numbers ....................................................................................................................................22
8.
Revision History.........................................................................................................................................23
9.
Contact.......................................................................................................................................................23
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
1. Pinout and Schematic
1.1.
YI_5
YI_4
YI_3
37
36
35
34
YI_0
YI_6
38
YI_1
YI_7
39
YI_2
YI_8
33
32
31
1
30
GND
XI_15
2
29
XI_7
XI_14
3
28
XI_6
XI_13
4
27
XI_5
XI_12
5
26
XI_4
XI_11
6
25
XI_3
XI_10
7
24
XI_2
XI_9
8
23
XI_1
XI_8
9
22
XI_0
GND
10
21
AVDD
GSL168X
13
14
15
16
17
18
19
20
GPIO0
GPIO1
VDDIO
IRQ
GND
Shutdown
VTNC
12
SCL
11
SDA
6
40
AVDD
1V8_OUT
1
2
3
4
5
6
YI_9
1.2.
Pinout Configuration
Pinout Description
Pin Name
TYPE
Comment
AVDD
XI_15
XI_14
XI_13
XI_12
XI_11
P
O
O
O
O
O
Analog power supply
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
XI_10
XI_9
XI_8
GND
1V8_OUT
SDA
SCL
GPIO0/RXD
GPIO0/TXD
VDDIO
IRQ
GND
~Shutdown
VTNC
AVDD
XI_0
XI_1
XI_2
XI_3
XI_4
XI_5
XI_6
XI_7
GND
YI_0
YI_1
YI_2
YI_3
YI_4
YI_5
YI_6
YI_7
YI_8
YI_9
O
O
O
P
O
I/OD
I
I/O
I/O
P
O
P
I
O
P
O
O
O
O
O
O
O
O
P
I
I
I
I
I
I
I
I
I
I
Sensor driving line
Sensor driving line
Sensor driving line
Ground
Power up reset
I2C data line
I2C clock line
Uart or GPIO pin
Uart ot GPIO pin
IO Power supply
Interrupt
Ground
Power down control pin
Not connected
Analog power supply
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
Sensor driving line
Ground
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
Sensor sensing line
I
Input only
I/O
Input and output
O
Output only
OD
Open drain output
P
Ground or Power
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
1.3.
Schematic
The 1V8_OUT is the 1.8v power supply from GSL168X. The GSL168X IO is 1.8v and 3.3v compatible. If
the IO voltage in the system is 1.8v, R6 is needed and R5 is not needed. If the IO voltage in the system is
2.8 or 3.3v, then R5 is needed and R6 is not.
2. Overview
2.1.
Introduction
The GSL168X is a highly integrated capacitive screen monothetic multi-touch controller IC.
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
ADC
The GSL168X uses a unique mutual capacitive sensing technology. It allows the measurement of
up to 192 nodes in less than 1ms. GSL168X’s capacitive sensor is designed to work with a big range of
sensor selections, including single or two layer sensor glass or film, strip or diamond or their varying
sensor patterns, thin or thick ITO layers.
The GSL168X’s sophisticated anti-EMI signal processing technology make it completely immune
to all kinds of interferences including these from LCD, RF, power supply and environments. This makes
GSL168X be able to adapt to all kinds of phone design.
Equipped with a powerful 32-bit RISC CPU, GSL168X can accurately estimate the weight and
center of up to 10 finger touches, achieving zero-delay finger tracking with very soft-touch feeling.
The GSL168X uses a patented auto-tuning and auto-calibration technology which significantly
reduced the design-in cycle and enabled a very simple host interface. What’s more, the auto-track/fine
tune technology used in GSL168X enable it real-time compensate the performance variance due to
environment temperature and moisture changes.
2.2.
Resources
The following tools are provided together with GSL168X datasheet
 Silead Ctouch Testing Suite and User Guide
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
It includes the complete production testing suite PC tools and its user guide to assist the touch
panel module vendor to design and test the touch module using GSL168X.
 Silead Ctouch Configure Suite and Application note
It includes the PC tool to program the touch module and generate the configuration files to
assist the touch panel module vendor and phone vendor to customize the touch panel module.
3. Capacitive touch Basics
3.1.
Sensor and Electrode construction
A touchscreen is usually constructed from a number of transparent electrodes, typically on a
glass or film substrate. Electrodes are normally formed by etching a material called Indium Tin Oxide
(ITO) which is high optical clarity and varying sheet resistance. The ITO is etched to form X strip and Y
strip shown in the following diagram. The adjacent X/Y nodes form the mutual capacitive sensors.
Figure
Thicker ITO yields lower levels of resistance (perhaps tens to hundreds of ohms/square) at the
expense of reduced optical clarity. Lower levels of resistance are generally more compatible with
capacitive sensing. Thinner ITO leads to higher levels of resistance (perhaps hundreds to thousands of
ohms/square) with some of the best optical characteristics.
Long thin features, like interconnecting tracks, formed in ITO, can inhibit the capacitive sensing
function due to the excessive RC time constants formed between the resistance of the track and the
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
capacitance of the electrode to ground. In such cases, ITO tracks should be replaced by screen printed
conductive inks (non-transparent) outside of the viewing area of the touchscreen.
A range of trade-offs also exist with regard to the number of layers and different patterns used
for construction. A single-layer ITO in diamond pattern or others offer a better clarity and cost
performance. However, the exposure of sensing channel to LCD screen makes it vulnerable to LCD
interference. A shield layer is sometimes added in the other side if the sensor glass/film to shield the
LCD interference.
Two-layer designs usually offers a more favorable RC time constant and the bottom layer can
shield the LCD interference in some degree if it’s used as the driving channels.
GSL168X is designed to work with all the existing single or two-layer design, glass or film,
diamond or strip patterns or their variance, and a wide range of RC time constant. The highly
automatically tuning and calibration technology used in GSL168X reduce the effort to change sensor
glass/film to the minimum.
GSL1688 is specially designed for the single layer ITO multi-touch mutual capacitive sensor.
These kinds of sensor have only one layer ITO, no need of metal bridge. It significantly simplifies the
mutual capacitive sensor production process. However, these sensors have a very high line resistance.
The GSL1688 can support up to 150K ohm line resistance which allows the use of thin ITO layer on film
whose square resistance is as big as 150 ohm.
3.2.
Scanning Sequence
GSL168X supports up to 16 scanning channel and 10 sensing channels. The scanning channels are
scanned in sequence. However, the scan order is fully programmable. The sensing channels are full
parallelism. The channels are scanned by measuring capacitive changes at the intersections formed
between X0 and Y0 – Yn, then the intersections between X1 and Y0 – Yn, and so on, until all X and Y
combinations have been measured.
GSL168X can be configured in various ways, it is possible to disable some scanning or sensing
channels so that they are not scanned at all. This can be used to improve overall scanning time.
Although the sensing channels are parallel, the data order in the memory of each channel is fully
programmable. This provide the maximum flexibility to the FPC or PCB design. User can program the
scanning order or sensing data order through the Silead Ctouch Configure Suite or update the GSL168X
configuration file directly.
3.3.
Touchscreen sensitivity
Sensitivity of touchscreens can vary across the extents of the electrode pattern due to natural
differences in the parasitic of the interconnections, control chip, and so on. An important factor in the
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
uniformity of sensitivity is the electrode design itself. It is a natural consequence of a touchscreen
pattern that the edges form a discontinuity and hence tend to have a different sensitivity. The
electrodes at the far edges do not have a neighboring electrode on one side and this affects the electric
field distribution in that region. GSL168X auto compensate the sensitivity inconsistence for the whole
touchscreen.
The mechanical stackup refers to the arrangement of material layers that exist above and below a
touchscreen. The arrangement of the touchscreen in relation to other parts of the mechanical stackup
has an effect on the overall sensitivity of the screen. GSL168X technology has an excellent ability to
operate in the presence of ground planes close to the sensor.
Front panel dielectric material has a direct bearing on sensitivity. Plastic front panels are usually
suitable up to about 1.5 mm, and glass up to about 3 mm (dependent upon the screen size and layout).
The thicker the front panel, the lower the signal-to-noise ratio of the measured capacitive changes and
hence the lower the resolution of the touchscreen. In general, glass front panels are near optimal
because they conduct electric fields almost twice as easily film. GSL168X works well with either the
glass or film front panels.
4. Detail Operation
4.1.
Power Up and Reset
GSL168X takes a single power supply ranging from 2.6v~3.3v. There is an internal Power-on
Reset (POR) in the device. After power-up, the device takes 5 ms before it is ready to work. In order to
effect a proper POR Vdd must drop to below 1.6V.
After the chip experiences a Power-on-reset, it asserts the IRQ line to signal to the host that a
message is available. The reset flag is set in the Message Processor object( refer to GSL168X Application
notes for details) to indicate to the host that it has just completed a reset cycle. This bit can be used by
the host to detect any unexpected power breakout events and so allow it to take any necessary
corrective actions, such as reconfiguration.
A software reset command can be used to reset the chip (refer to the GSL168X Application
notes). A software reset takes ~1 ms. The reset event caused by software reset or RESET pin will not
trigger the Power-on-reset message to host.
4.2.
Calibration
Calibration is the process by which the sensor chip assesses the background capacitance on each
channel. Channels are only calibrated on power-up and when:
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller

the channel is held in detect for longer than the Touch Automatic Calibration setting

the signal delta on a channel is at least the touch threshold in the anti-touch direction, while no
other touches are present on the channel matrix

the user issues a recalibrate command
4.3.
Communication
4.3.1. Communications Protocol
The GSL168X uses an I2C-compatible interface for communication. The device is not designed to
be polled, as it only presents data packets when internal changes have occurred. The IRQ line going
active signifies that a new data packet is available.
4.3.2. I2C-compatible Addresses
The GSL168X supports a single I2C-compatible device addresses, 0x40. It is shifted left to form
the SLA+W or SLA+R address when transmitted over the I2C-compatible interface, as shown in table
below.
Format of SLA+W and SLA+R
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Address: 0x40
Bit 1
Bit 0
Read/Write
4.3.3. Writing to the Device
A WRITE cycle to the device consists of a START condition followed by the I2C-compatible
address of the device (SLA+W). The next byte is the address of the location into which the writing starts.
Subsequent bytes in a multibyte transfer – the actual data – are written to the location of the
address pointer, location of the address pointer +1, location of the address pointer + 2, and so on.
The WRITE operation ends with the STOP condition on the I2C-compatible bus. A new WRITE
cycle involves sending another address pointer. Note that the WRITE cycle must end with a STOP
condition; the GSL168X may not respond correctly if a cycle is terminated by a new START condition.
Figure below shows an example of writing four bytes of data to contiguous addresses starting at 0x80.
Example of a Four-byte, 0x12345678 Write To Address 0x80
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
4.3.4. Reading from the Device
To read from the device, usually two I2C-compatible bus activities take place: the first is an
I2Ccompatible write to set the address pointer, and the second is the actual I2C-compatible read to
receive the data. The address pointer returns to its starting value when the READ cycle’s STOP condition
is detected.
It is not necessary to set the address pointer before every read. The address pointer is updated
automatically after every read operation so, if the reads occur in order, the address pointer will be
correct.
The WRITE and READ cycles consist of a START condition followed by the I2C-compatible address of the
device (SLA+W or SLA+R respectively). Each cycle must end with a STOP condition; the GSL168X may not
respond correctly if a cycle is terminated by a new START condition.
Figure below shows the I2C-compatible commands to read four bytes from address 0x80.
Example of a Four-byte Read From Address 0x80
4.3.5. SDA, SCL
The I2C-compatible bus transmits data and clock with SDA and SCL, respectively. These are opendrain; that is, I2C-compatible master and slave devices can only drive these lines low or leave them open.
The termination resistors (Rp) pull the line up to Vdd if no I2C-compatible device is pulling it down.
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
The termination resistors commonly range from 1 k ohm to 10 k ohm and should be chosen so
that the rise times on SDA and SCL meet the I2C-compatible specifications.
4.3.6. IRQ
The IRQ pin is an active-high output pin that is used to alert the host that a new message is
available. This provides the host with an interruptstyle interface with the potential for fast response
times and reduces the need for wasteful I2C-compatible communications.
The host should ALWAYS use the IRQ pin as an indication that a message is available to read; the
host should not read the Message at any other time (for example, continually poll the Message). As an
error checking mechanism, if the chip has to read when the IRQ line is not asserted, a double read is
recommended and the consistent reading results can be used as an indication that no co-occurrence of
read and update of message happen.
4.4.
Operation mode
The GSL168X operates at one shutdown mode and three running modes.
4.4.1. Shutdown mode
The device has a SHUTDOWN pin that, when pull low, will put GSL168X in deepsleep mode, in
which the device consume the least power. After the SHUTDOWN pin is disserted, the device is wake up
from the deepsleep mode and ready to take the START command from host to get into the running
modes.
It is recommended to connect the SHUTDOWN pin to a GPIO of host controller. The host can put
GSL168X into deepsleep mode when the touch screen is not needed to be running.
4.4.2. Running modes
When GSL168X is active, it operates on a combination of three fixed cycle times. There is one
acquisition per cycle. When no channels are touched, the cycle time is given by the GREEN_SCANDELAY
setting in the device configure file. Every cycle, one acquisition is made and the device then sleeps for
the remainder of the cycle.
If a channel is touched, the device turn to active mode and the cycle changes to the
ACTIVE_SCANDELAY setting for a faster response. It remains in this active mode until the
ACTIVE_TIMEOUT has expired after the last touch, the device enters the low speed scan mode and the
cycle changes to LOW_SCANDELAY setting for a slower response. If a channel is touched, the device will
return to the active mode, otherwise, it stays at low speed scan mode until LOW_TIMEOUT has expired
and then enter the green mode in which the device monitor the touch panel at the much slower speed.
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GSL1680, 1688 Capacitive Touchscreen Controller
The touch reporting rate of the active, low speed and green modes, timeout to transit from one
mode to the others all are configurable through Silead Ctouch Configure Suite or GSL168X configuration
file.
The default frame reporting rate of the active, low speed and green mode are, 60, 30 and 5
respectively. The maximum allowed reporting rate is 200 frames/s and the minimum allowed reporting
rate is 0.5 frames/s. In each frames, multi-touch can be reported.
4.5.
Circuit Component
4.5.1. Bypass Capacitors
A 100 nF and a 1 μF ceramic bypass capacitor are highly recommended on each of Vdd and
AVdd supplies (that is, 4 capacitors in total). The PCB traces connecting the capacitors to the pins of the
device must not exceed 5 mm in length to limit any stray inductance that would reduce filtering
effectiveness.
4.5.2. PCB Cleanliness
Modern no-clean-flux is generally compatible with capacitive sensing circuits.
If a PCB is reworked in any way, clean it thoroughly to remove all traces of the flux residue
around the capacitive sensor components. Dry it thoroughly before any further testing is conducted.
4.6.
Signal processing
4.6.1. Anti-EMI interference
The touch panel receives the interference from LCD, RF and power supply. Any noise may be big
enough to overwhelm the useful touch information and cause false reports.
GSL168X uses patented technology to filter out these EMI interferences and recover the useful
information from the corrupted signal in multiple stages. GSL168X’s anti-EMI technology makes it
completely immune to these EMI interferences even in a not-well designed phone.
4.6.2. Floating Terminal
If a phone or pad terminal is placed in a table instead of being held in a human hand, false signal
maybe reported in these non-touched areas. This is due to the absence of the good common ground.
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
GSL168X is specially designed to filter out these false signals due to lack of good common
ground and there is no performance degeneration when the phone/pad using GSL168X is not held in a
body.
4.6.3. Inter Finger Interference
When two fingers, touching the panel, are close, it’s usually difficult to separate them and two
fingers may be treated as one and the wrong touch position may be reported.
GSL168X use an adjacent touch compensation technology to reduce the inter finger interference
and give a accurate touching count and positions even when two finger distance are smaller than the
1.5x distance of two driving lines or sensing lines..
4.6.4. Face and Water Suppression
The GSL168X has a mechanism to suppress false detections from a touchscreen incorporated
into a mobile device. For example, when water is on the touch screen, the user grips the device in their
hand or, in the case of a mobile phone, holds it close to their face.
Face suppression takes both the size and shape of a touch into consideration. By considering the
size of the touch, face suppression ensures that a small touch (such as from a finger) is allowed, whereas
a large touch (such as from a face) is suppressed. By considering the shape of a touch – or rather the
aspect ratio of a touch – face suppression ensures that a narrow shape (typically a finger) is allowed,
whereas a wide shape (such as that of a face) is suppressed.
The big area Water spot in the touch panel is similar to the face touch but the shape is more
random. Water suppression ensures that a small touch is allowed, whereas a large touch is suppressed.
The finger touch outside of the water area is not affected.
5. Getting Start with GSL168X
5.1.
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Connection with Host
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
GSL168X connect to host controller through 4 pins besides the power supply. The power supply
range from 2.6v to 3.6v.
SDA and SCL is the I2C compliant communication interface. Both pins are open drain. IRQ is the
interrupt signal to host to indicate a new message is ready.
SHUTDOWN pin is recommended to connect to the GPIO of host. If pull the SHUTDOWN pin low
by the host, the GSL168X will enter the deepsleep state to consume the least power. To wake up
GSL168X from deepsleep, host has to release SHUTDOWN to high and send a START_COMMAND to
GSL168X to kick it off. If SHUTDOWN feature is not needed, the pin can be leave unconnected.
5.2.
Configuring the Device
GSL168X has a very high configurability. The configuration is done through the GSL168X
Configuration File, which can be modified directly or be generated by the Silead Ctouch Configure Suite.
The Configuration File will be loaded by the GSL168X Configure API and program the device
automatically when the device is initialized.
The detail can be referred to Silead Ctouch Configure Suite application notes.
5.3.
Communications With the Host
GSL168X has a memory map register set to communicate with the host. These registers include
the GSL168X event message, touch information, and the command queue to accept host instruction. A
predefined API ( refer to GSL168X Application Notes) example is provided together with GSL168X to
assist communications.
5.4.
Steps to Start GSL168X
When power up, IRQ line will go low and the interrupt message in the memory mapped register
show it’s a power up interrupt. The host driver will then start the GSL168X initialization in which the
GSL168X configurable File is loaded to program the device.
Once the configurable is finished, host will start the GSL168X. GSL168X will go through the
calibration cycle and enter green mode and start monitoring the touch screen. If a touch is detected,
GSL168X will transit to active mode and IRQ will go high and interrupt host to report a touch event.
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Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
6. Specification
6.1.
Operating Conditions
Parameter
Min
Typ
Max
AVDD
2.6v
2.8v
3.3v
Supply ripple + noise
300mV
-20oC
Operating temp
+85oC
DC Specification
6.2.
Description
Parameter
Idd
Vil
Average supply current,
60Hz, 1 touch
Low Input Logic Level
Vih
High Input Logic Level
Vol
Low output voltage
Voh
High output voltage
Iil
Input leakage current
6.3.
Min
Typ
Max
Unit
-0.5
0.3 Vdd
V
0.7 Vdd
Vdd+0.5
V
8mA
0.2Vdd
0.8Vdd
V
<0.001
1
uA
I2C-compatible Bus Specifications
Parameter
Operation
Address
0X40
Maximum bus speed (SCL)
400KHz
Hold time START condition
<650 ns
Setup time for STOP condition
<650 ns
SDA/SCL/ rise time
< 200 ns
19
+25oC
Silead Inc.
Capacitive Touchscreen Controller
Note
GSL1680, 1688 Capacitive Touchscreen Controller
6.4.
Power Consumption
Parameter
Operation
SHUTDOWN Mode
<30uA
Green Mode
<3mA
5 frame/s, charge time 5us
Low Scan Speed
< 6mA
30 frame/s, charge time 5us
Active Mode
<9 mA
60 frame/s, charge time 5us
6.5.
Note
Moisture Sensitivity Level
MSL Rating
Peak Body Temperature
Specification
MSL3
260oC
IPC/JEDEC-STD-020
20
Silead Inc.
Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
7. Package
7.1.
21
Mechanic Dimention
Silead Inc.
Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
7.2.
Marking
7.3.
Part Numbers
Part Number
Description
GSL168XQ40
40-pin 5x5 mm QFN RoHS compliant
22
Silead Inc.
Capacitive Touchscreen Controller
GSL1680, 1688 Capacitive Touchscreen Controller
8. Revision History
Revision Number
History
Revision A1.0 – Nov 2011
Initial release
Revision A1.6 – Oct 2012
Add GSL1688
9. Contact
上海浦东新区盛夏路 560 号 2 幢 1003 思立微电子 201203
Tel: 021-20221991 Fax: 021-20221996
Email: [email protected]
23
Silead Inc.
Capacitive Touchscreen Controller