CYPRESS CY8C20121

PRELIMINARY
CY8C20111, CY8C20121
CapSense Express™ - One Button and
Two Button Capacitive Controllers
1. Features
2. Overview
■
Capacitive Button Input tied to a Configurable Output
❐ Robust sensing algorithm
❐ High sensitivity, low noise
❐ Immunity to RF and AC noise
❐ Low radiated EMC noise
❐ Supports wide range of input capacitance, sensor shapes,
and sizes
■
Target Applications
❐ Printers
❐ Cellular handsets
❐ LCD monitors
❐ Portable DVD players
The CapSense Express™ controllers support two capacitive
sensing (CapSense) buttons and two general purpose outputs in
CY8C20121 and one CapSense button and one general
purpose output in CY8C20111. The device functionality is
configured through the I2C port and can be stored in on-board
nonvolatile memory for automatic loading at power on. The
digital outputs are controlled from CapSense inputs in factory
default settings, but are user configurable for direct control
through I2C.
■
Industry's Best Configurability
❐
❐
❐
❐
Custom sensor tuning
Output supports strong 20 mA sink current
Output state can be controlled through I2C or directly from
CapSense input state
Run time reconfigurable over I2C
■
Advanced Features
❐ Plug-and-play with factory defaults – tuned to support up to
1 mm overlay
❐ Nonvolatile storage of custom settings
❐ Easy integration into existing products – configure output to
match system
❐ No external components required
❐ World class free configuration tool
■
Wide Range of Operating Voltages
❐ 2.45V to 2.9V
❐ 3.10V to 3.6V
❐ 4.75V to 5.25V
■
I2C Communication
❐ Supported from 1.8V
❐ Internal pull up resistor support option
❐ Data rate up to 400 kbps.
2
❐ Configurable I C addressing
■
Industrial Temperature Range: –40°C to +85°C
■
Available in 8-Pin SOIC Package
Cypress Semiconductor Corporation
Document Number: 001-53516 Rev. **
•
The four key blocks that make up the CY8C20111 and
CY8C20121 controllers are: a robust capacitive sensing core
with high immunity against radiated and conductive noise,
control registers with nonvolatile storage, configurable outputs,
and I2C communications. The user can configure registers with
parameters needed to adjust the operation and sensitivity of the
CapSense buttons and outputs and permanently store the
settings. The standard I2C serial communication interface allows
the host to configure the device and read sensor information in
real time. I2C address is fully configurable without any external
hardware strapping.
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised May 20, 2009
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CY8C20111, CY8C20121
3. Pinouts
Figure 1. CY8C20111 Pin Diagram - 8 SOIC - 1 Button
Table 1. Pin Definitions – 8 SOIC- 1 Button
Pin No
Name
Description
1
VSS
2
I2C SCL
I2C Clock
3
I2C SDA
I2C Data
4
CS0
CapSense Input
5
NC
No Connect
6
DIG0
7
NC
8
VDD
Ground
Digital Output
No Connect
Supply Voltage
Figure 2. CY8C20121 Pin Diagram – 8 SOIC- 2 Button
Table 2. Pin Definitions – 8 SOIC- 2 Button
Pin No
Name
Description
1
VSS
2
I2C SCL
I2C Clock
3
I2C SDA
I2C Data
4
CS0
CapSense Input
5
CS1
CapSense Input
6
DIG0
Digital Output
7
DIG1
Digital Output
8
VDD
Supply Voltage
Ground
Document Number: 001-53516 Rev. **
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CY8C20111, CY8C20121
4. Typical Circuits
4.1 Circuit-1: One Button and One LED[1]
4.2 Circuit-2: One Button and One LED with I2C Interface
Note
1. The sensors are factory tuned to work with 1 mm plastic or glass overlay.
Document Number: 001-53516 Rev. **
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CY8C20111, CY8C20121
4.3 Circuit-3: Two Buttons and Two LEDs with I2C Interface
4.4 Circuit-4: Compatibility with 1.8V I2C Signaling[2]
Note
2. 1.8V < VDD_I2C < VDD_CE and 2.4V < VDD_CE < 5.25V.
Document Number: 001-53516 Rev. **
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CY8C20111, CY8C20121
4.5 Circuit-5: Powering Down CapSense Express Device for Low Power Requirements
Output
enable
Output
LDO
VDD
I2C Pull
UPs
LED
Master
Or
Host
CapSense Express
SDA
I2C
BUS
SCL
For low power requirements, if Vdd is to be turned off, the above
concept can be used. The Vdds of CapSense Express, I2C pull
ups, and LEDs must be from the same source. Turning off the
Vdd ensures that no signal is applied to the device while it is
unpowered. The I2C signals should not be driven high by the
master in this situation. If a port pin or group of port pins can cater
to the power supply requirement of the circuit, the LDO can be
avoided.
5. Operating Modes
6. I2C Interface
The CapSense Express devices support the industry standard
I2C protocol, which can be used to:
■
Configure the device
■
Read the status and data registers of the device
■
Control device operation
■
Execute commands
5.1 Normal Mode
The I2C address can be modified during configuration.
In normal mode of operation, the acknowledgment time is
optimized. The timings remain approximately the same for
different configurations of the slave. To reduce the acknowledgment times in normal mode, the registers 0x07, 0x08, 0x11,
0x50, 0x51, 0x5C, 0x5D are given only read access. Writing to
these registers can be done only in setup mode.
6.1 I C Device Addressing
5.2 Setup Mode
2
The device uses a seven bit addressing protocol. The I2C data
transfer is always initiated by the master sending one byte
address; first 7-bit contains address and LSb indicates the data
transfer direction. Zero in the LSb indicates the write transaction
form master and one indicates read transfer by the master.
Table 3 shows example for different I2C addresses.
All registers have read and write access (except those which are
read only) in this mode. The acknowledgment times are longer
compared to normal mode. When CapSense scanning is
disabled (command code 0x0A in command register 0xA0), the
acknowledgment times can be improved to values similar to the
normal mode of operation.
Table 3. I2C Addresses
7 Bit Slave Address (in Dec)
D7
D6
D5
D4
D3
D2
D1
D0
8 Bit Slave Address (in Hex)
1
0
0
0
0
0
0
1
0(W)
02
1
0
0
0
0
0
0
1
1(R)
03
75
1
0
0
1
0
1
1
0(W)
96
75
1
0
0
1
0
1
1
1(W)
97
Document Number: 001-53516 Rev. **
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6.2 I2C Clock Stretching
“Clock stretching” or “bus stalling” in I2C communication protocol
is a state in which the slave holds the SCL line low to indicate
that it is busy. In this condition, the master is expected to wait
until the SCL is released by the slave.
When an I2C master communicates with the CapSense Express
device, the CapSense Express stalls the I2C bus after the
reception of each byte (that is, just before the ACK/NAK bit) until
processing of the byte is complete and critical internal functions
are executed. Use a fully I2C compliant master to communicate
with the CapSense Express device.
An I2C master which does not support clock stretching (a bit
banged software I2C Master) must wait for a specific amount of
time specified (as shown in the section Format for Register Write
and Read) for each register write and read operation before the
next bit is transmitted. It is mandatory to check the SCL status (it
should be high) before I2C master initiates any data transfer with
CapSense Express. If the master fails to do so and continues to
communicate, the communication is erroneous.
The following diagrams represent the ACK time delays shown in
the Register Map on page 7.
Figure 3. Write ACK Time Representation
Figure 4. Read ACK Time Representation
6.3 Format for Register Write and Read
Register write format.
Start
Slave Addr + W
A
Reg Addr
A
Data
A
Register read format.
Start
Slave Addr + W
Start
Slave Addr + R
A
A
Reg Addr
Data
A
A
Stop
Data
A
Legends:
Master
Slave
Data
.....
A
.....
Data
Data
N
A
Stop
Stop
A - ACK
N- NAK
7. Registers
Table 4. Register Conventions
Convention
RW
R
WPR
FD
Description
Register have both read and write access
Register have only read access
Write register with pass code
Factory defaults
Document Number: 001-53516 Rev. **
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CY8C20111, CY8C20121
Table 5. Register Map
Writable
Only in
Setup
Mode[3]
Factory Default
Values of Registers
(in Hex)
I2C Max ACK
Time in Normal
Mode (ms)[5]
Register
Address
(in Hex)
Access
OUTPUT_PORT
04
W
CS_ENABLE
07
RW
DIG_ENABLE
08
RW
SET_STRONG_DM
11
RW
OP_SEL_0
1C
RW
LOGICAL_OPR_INPUT0
1E
RW
OP_SEL_1[4]
21
RW
LOGICAL_OPR_INPUT1[4]
23
RW
CS_NOISE_TH
4E
RW
CS_BL_UPD_TH
4F
RW
CS_SETL_TIME
50
RW
Yes
CS_OTH_SET
51
RW
Yes
00
00
CS_HYSTERISIS
52
RW
0A
0A
0.11
CS_DEBOUNCE
53
RW
03
03
CS_NEG_NOISE_TH
54
RW
14
14
CS_LOW_BL_RST
55
RW
14
CS_FILTERING
56
RW
20
CS_SCAN_POS_0
5C
RW
Yes
00
CS_SCAN_POS_1[4]
5D
RW
Yes
CS_FINGER_TH_0
66
RW
CS_FINGER_TH_1[4]
67
RW
CS_IDAC_0
70
RW
CS_IDAC_1[4]
71
RW
I2C_ADDR_LOCK
79
RW
DEVICE_ID
7A
R
Name
I2C Max
ACK Time in
Setup
Mode
(ms)[5]
Page No.
1 Button
2 Button
01
03
Yes
01
03
11
9
Yes
01
03
11
10
Yes
01
03
11
10
82
82
0.12
11
12
01
01
0.12
11
12
82
0.12
11
12
02
0.12
11
12
28
0.11
11
13
64
64
0.11
A0
A0
28
64
0.10
9
11
13
35
13
35
14
11
14
0.11
11
15
0.11
11
15
14
0.11
11
15
20
0.11
11
16
00
11
16
01
11
16
64
0.14
11
17
64
0.14
11
17
0A
0.14
11
17
0A
0.14
11
17
00
00
0.11
11
17
11
21
0.11
11
18
0A
DEVICE_STATUS
7B
R
03
03
0.11
11
18
I2C_ADDR_DM
7C
RW
00
00
0.11
11
19
CS_READ_BUTTON
81
RW
00
00
0.12
11
19
CS_READ_BLM
82
R
00
00
0.12
11
20
CS_READ_BLL
83
R
00
00
0.12
11
20
CS_READ_DIFFM
84
R
00
00
0.12
11
20
CS_READ_DIFFL
85
R
00
00
0.12
11
20
CS_READ_RAWM
86
R
00
00
0.12
11
20
CS_READ_RAWL
87
R
00
00
0.12
11
20
CS_READ_STATUS
88
R
00
00
0.12
11
21
COMMAND_REG
A0
W
00
00
0.10
11
21
Notes
3. These registers are writable only after entering into setup mode. All other registers are available for read and write in normal and setup mode.
4. These registers are available only in CY8C20121 device.
5. The Ack times specified are 1x I2C Ack times.
Document Number: 001-53516 Rev. **
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Table 6. CapSense Express Commands
Command [5]
W 00 A0 00
Executable
Mode
Description
Duration the Device is NOT Accessible after ACK (in ms)[5]
Get firmware revision
Setup/Normal
0
W 00 A0 01
Store current configuration to NVM
Setup/Normal
120
W 00 A0 02
Restore factory configuration
Setup/Normal
120
W 00 A0 03
Write NVM POR defaults
Setup/Normal
120
W 00 A0 04
Read NVM POR defaults
Setup/Normal
5
W 00 A0 05
Read current configurations (RAM)
Setup/Normal
5
W 00 A0 06
Reconfigure device (POR)
Setup
5
W 00 A0 07
Set Normal mode of operation
Setup/Normal
0
W 00 A0 08
Set Setup mode of operation
Setup/Normal
0
W 00 A0 09
Start scan
Setup/Normal
10
W 00 A0 0A
Stop scan
Setup/Normal
5
W 00 A0 0B
Get CapSense scan status
Setup/Normal
0
Note
6. ‘W’ indicates the write transfer. The next byte of data represents the 7 bit I2C address.
Document Number: 001-53516 Rev. **
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7.1 OUTPUT_PORT
Output Port Register
OUTPUT_PORT: 04h
1 Button
7
6
5
4
3
2
1
0
Access: FD
W:01
Bit Name
DIG[0]
2 Button
7
6
5
4
3
2
1
0
Access: FD
W:03
Bit Name
DIG[1:0]
This register is used to write data to DIG output port. Pins defined as output of combinational logic (in OP_SEL_x register) cannot be
changed using this register.
Bit
Name
Description
1:0
DIG [1:0]
A bit set in this register sets the logic level of the output.
0
Logic ‘0’
1
Logic ‘1’
7.2 CS_ENABLE
Select CapSense Input Register
CS_ENABLE: 07h
(Writable only in Setup mode)
1 Button
7
6
5
4
3
2
1
0
Access: FD
RW:01
Bit Name
CS[0]
2 Button
7
6
5
4
3
2
1
0
Access: FD
RW:03
Bit Name
CS[1:0]
This register is used to enable CapSense inputs. This register should be set before setting finger threshold (0x66, 0x67) and
IDAC setting (0x70, 0x71) registers.
Bit
Name
Description
1:0
CS [1:0]
These bits are used to enable CapSense inputs.
0
Disable CapSense input
1
Enable CapSense input
Document Number: 001-53516 Rev. **
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7.3 DIG_ENABLE
Select DIG Output Register
GPO_ENABLE: 08h
(Writable only in Setup mode)
1 Button
7
6
5
4
3
2
1
0
Access: FD
RW:01
Bit Name
DIG[0]
2 Button
7
6
5
4
3
2
1
0
Access: FD
RW:03
Bit Name
DIG [1:0]
This register is used to enable DIG (Digital) outputs. If DIG output is enabled, the strong drive mode register (11h) should also be set.
If DIG output is disabled the drive mode of these pins is High Z.
Bit
Name
Description
1:0
DIG [1:0]
These bits are used to enable DIG outputs.
0
Disable DIG output
1
Enable DIG output
7.4 SET_STRONG_DM
Sets Strong Drive Mode for DIG Outputs.
SET_STRONG_DM: 11h
(Writable only in Setup mode)
1 Button
7
6
5
4
3
2
1
0
Access: FD
RW:01
Bit Name
DM [0]
2 Button
7
6
5
4
3
2
1
0
Access: FD
RW:03
Bit Name
DM [1:0]
This register sets strong drive mode for DIG (Digital) outputs. To set strong drive mode the pin should be enabled as GP output.
Bit
Name
Description
1:0
DM [1:0]
These bits are used to set the strong drive mode to DIG outputs.
0
Strong drive mode not set
1
Strong drive mode set
Document Number: 001-53516 Rev. **
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Figure 5. CY8C20111 Digital Logic Diagram
OUTPUT_PORT [0]
LOGICAL_OPR_INPUT0 [0]
A
INVERSION
LOGIC
ENB
AND / OR
Logic selection
CS0
DIG0
B
S
OP_SEL_0 [0]
OP_SEL_0 [7]
OP_SEL_0 [1]
Figure 6. CY8C20121 Digital Logic Diagram
LOGICAL_OPR_INPUTx [0]
OUTPUT_PORT [x]
ENB
A
CS0
A
LOGICAL_OPR_INPUTx [1]
ENB
INVERSION
LOGIC
AND / OR
Logic selection
AND / OR
Logic selection
DIGx
B
S
B
S
CS1
OP_SEL_x [7]
OP_SEL_x [0]
OP_SEL_x [1]
INPUT SELECTION LOGIC
Document Number: 001-53516 Rev. **
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7.5 OP_SEL_x
Logic Operation Selection Registers
OP_SEL_0: 1Ch
OP_SEL_1: 21h (Not available for 1 Button)
1/2Button
7
Access: FD
Bit Name
6
5
4
3
2
1
0
RW: 0
RW: 0
RW: 0
Op_En
InvOp
Operator
This register is used to enable logic operation on GP outputs. OP_SEL_0 should be configured to get the logic operation output on
DIG0 output and OP_SEL_1 for DIG1 output. Write to these registers during the disable state of respective DIG output pins does not
have any effect.
The input to the logic operation can be selected in LOGIC_OPRX registers. The selected inputs can be ORed or ANDed. The output
of logic operation can also be inverted.
Bit
Name
7
Op_En
1
InvOp
0
Operator
Description
This bit enables or disables logic operation.
0
Disable logic operation
1
Enable logic operation
This bit enables or disables logic operation output inversion.
0
Logic operation output not inverted
1
Logic operation output inverted
This bit selects which operator should be used to compute logic operation.
0
Logic operator OR is used on inputs
1
Logic operator AND is used on inputs
7.6 LOGICAL_OPR_INPUTx
Selects Input for Logic Operation
LOGICAL_OPR_INPUT0: 1Eh
LOGICAL_OPR_INPUT0
1 Button
7
Access: FD
Bit Name
2 Button
Access: FD
Bit Name
7
LOGICAL_OPR_INPUT1: 23h (Not available for 1 button)
6
5
4
3
2
1
0
RW:01
CSL[0]
6
5
4
3
2
1
0
RW:01
CSL [1:0]
LOGICAL_OPR_INPUT1
2 Button
7
Access: FD
Bit Name
6
5
4
3
2
1
0
RW:02
CSL [1:0]
These registers are used to give the input to logic operation block. The inputs can be only CapSense input status.
Bit
Name
Description
1:0
CSL [1:0]
These bits selects the input for logic operation block.
Document Number: 001-53516 Rev. **
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7.7 CS_NOISE_TH
Noise Threshold Register
CS_NOISE_TH: 4Eh
1/2 Button
7
6
5
4
3
Access: FD
RW:28
Bit Name
NT[7:0]
2
1
0
This register sets the noise threshold value. For individual sensors, count values above this threshold do not update the baseline.
This count is relative to baseline. This parameter is common for all sensors.
The range is 3 to 255 and it should satisfy the equation NT < Min (Finger Threshold – Hysteresis – 5). Recommended value is 40%
of finger threshold.
Bit
Name
Description
7:0
NT [7:0]
These bits are used to set the noise threshold value.
7.8 CS_BL_UPD_TH
Baseline Update Threshold Register
CS_BL_UPD_TH: 4Fh
1/2 Button
7
6
5
4
3
Access: FD
RW:64
Bit Name
BLUT[7:0]
2
1
0
When the new raw count value is above the current baseline and the difference is below the noise threshold, the difference between
the current baseline and the raw count is accumulated into a “bucket.” When the bucket fills, the baseline increments and the bucket
is emptied. This parameter sets the threshold that the bucket must reach for the baseline to increment. In other words, lower value
provides faster baseline update rate and vice versa. This parameter is common for all sensors.
The range is 0 to 255.
Bit
Name
7:0
BLUT [7:0]
Description
These bits set the threshold that the bucket must reach for baseline to increment.
7.9 CS_SETL_TIME
Settling Time Register
CS_SETL_TIME: 50h
(Writable only in Setup mode)
1/2 Button
7
Access: FD
Bit Name
6
5
4
3
RW:A0
STLNG_TM[7:0]
2
1
0
The settling time parameter controls the duration of the capacitance-to-voltage conversion phase. The parameter setting controls a
software delay that allows the voltage on the integrating capacitor to stabilize. This parameter is common for all sensors.
This register should be set before setting finger threshold (0x66, 0x67) and IDAC setting (0x70, 0x71) registers.
The range is 2 to 255.
Bit
Name
7:0
STLNG_TM [7:0]
Document Number: 001-53516 Rev. **
Description
These bits are used to set the settling time value.
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7.10 CS_OTH_SET
CapSense Clock Select, Sensor Auto Reset Register
CS_OTH_SET: 51h
(Writable only in Setup mode)
1/2 Button
7
6
5
4
3
Access: FD
RW: 00
RW: 0
Bit Name
CS_CLK[1:0]
Sns_Ar
2
1
0
The registers set the CapSense module frequency of operation and enables or disables the sensor auto reset.
CS_CLK bits provides option to select variable clock input for the CapSense block. A sensor design having higher paratactic requires
lower clock for better performance and vice versa.
Sensor Auto Reset determines whether the baseline is updated at all times or only when the signal difference is below the noise
threshold. When set to ‘1’ (enabled), the baseline is updated constantly. This setting limits the maximum time duration of the sensor,
but it prevents the sensors from permanently turning on when the raw count suddenly rises without anything touching the sensor. This
sudden rise can be caused by a large power supply voltage fluctuation, a high energy RF noise source, or a very quick temperature
change. When the parameter is set to ‘0’ (disabled), the baseline is updated only when raw count and baseline difference is below
the noise threshold parameter. This parameter may be enabled unless there is a demand to keep the sensors in the on state for a
long time. This parameter is common for all sensors.
Bit
Name
Description
6:5
CS_CLK[1:0]
These bits selects the CapSense clock.
CS_CLK[1:0]
00
01
10
11
3
Sns_Ar
Frequency of Operation
IMO
IMO/2
IMO/4
IMO/8
This bit is used to enable or disable sensor auto reset.
0
Disable Sensor auto reset
1
Enable Sensor auto reset
7.11 CS_HYSTERISIS
Hysteresis Register
CS_HYSTERISIS: 52h
1/2 Button
7
6
5
4
3
Access: FD
RW:0A
Bit Name
HYS[7:0]
2
1
0
The Hysteresis parameter adds to or subtracts from the finger threshold depending on whether the sensor is currently active or
inactive. If the sensor is off, the difference count must overcome the ‘finger threshold + hysteresis’. If the sensor is on, the difference
count must go below the ‘finger threshold – hysteresis’. It is used to add debouncing and “stickiness” to the finger detection algorithm.
This parameter is common for all sensors.
Possible values are 0 to 255. However, the setting must be lower than the finger threshold parameter setting. Recommended value
for hysteresis is 15 percent of finger threshold.
Bit
Name
7:0
HYS [7:0]
Document Number: 001-53516 Rev. **
Description
These bits are used to set the hysteresis value.
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7.12 CS_DEBOUNCE
Debounce Register.
CS_DEBOUNCE: 53h
1/2 Button
7
6
5
4
3
Access: FD
RW:0A
Bit Name
DB[7:0]
2
1
0
The Debounce parameter adds a debounce counter to the ‘sensor active transition’. For the sensor to transition from inactive to active,
the consecutive samples of difference count value must stay above the ‘finger threshold + hysteresis’ for the number specified. This
parameter is common for all sensors.
Possible values are 1 to 255. A setting of ‘1’ provides no debouncing.
Bit
Name
7:0
DB [7:0]
Description
These bits are used to set the debounce value.
7.13 CS_NEG_NOISE_TH
Negative Noise Threshold Register
CS_NEG_NOISE_TH: 54h
1/2 Button
7
6
5
4
3
Access: FD
RW:0A
Bit Name
NNT[7:0]
2
1
0
This parameter adds a negative difference count threshold. If the current raw count is below the baseline and the difference between
them is greater than this threshold, the baseline is not updated. However, if the current raw count stays in the low state (difference
greater than the threshold) for the number of samples specified by the Low Baseline Reset parameter, the baseline is reset. This
parameter is common for all sensors.
Bit
Name
7:0
NNT [7:0]
Description
These bits are used to set the negative noise value.
7.14 CS_LOW_BL_RST
Low Baseline Reset Register
CS_LOW_BL_RST: 55h
1/2 Button
7
Access: FD
Bit Name
6
5
4
3
2
1
0
RW:0A
LBR[7:0]
This parameter works together with the Negative Noise Threshold parameter. If the sample count values are below the baseline minus
the negative noise threshold for the specified number of samples, the baseline is set to the new raw count value. It essentially counts
the number of abnormally low samples required to reset the baseline. It is generally used to correct the finger-on-at-startup condition.
This parameter is common for all sensors.
Bit
Name
7:0
LBR [7:0]
Document Number: 001-53516 Rev. **
Description
These bits are used to set the Low Baseline Reset value.
Page 15 of 34
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PRELIMINARY
CY8C20111, CY8C20121
7.15 CS_FILTERING
CapSense Filtering Register
CS_FILTERING: 56h
1/2 Button
7
Access: FD
RW: 0
RstBl
Bit Name
6
5
RW: 1
I2C_DS
4
RW: 0
Avg_En
3
2
1
0
RW: 00
Avg_Order[1:0]
This register provides an option for forced baseline reset and to enable and configure two different types of software filters.
Bit
Name
7
RstBl
5
I2C_DS
4
Avg_En
[1:0]
Description
This bit resets all the baselines and it is auto cleared to ‘0’.
0
All Baselines are not reset
1
All baselines are reset
When this bit is set to ‘1’ the CapSense scan sample is dropped if I2C communication
was active during scanning.
0
Disable the I2C drop sample filer
1
Enable the I2C drop sample filter
This bit enables average filter on raw counts.
0
Disable the average filter
1
Enable the average filter
These bits are used to select the number of CapSense samples to average:
Avg_Order[1:0]
Avg_Order[1:0] in Hex
00
01
10
11
Samples to Average
2
4
8
16
7.16 CS_SCAN_POS_x
Scan Position Registers
CS_SCAN_POS_0: 5Ch
(Writable only in Setup mode)
1/2 Button
7
6
5
4
3
2
1
0
Access: FD
RW: 0
Bit Name
Scan_Pstn
CS_SCAN_POS_1: 5Dh (Not available for 1 Button)
(Writable only in Setup mode)
2 Button
7
6
5
4
3
2
1
0
Access: FD
RW: 1
Bit Name
Scan_Pstn
This register is used to set the position of the sensors in the switch table for proper scanning sequence because the CapSense sensors
are scanned in sequence.
This register should be set after setting 0x07, 0x50, and 0x51 registers.
Bit
Name
0
Scan_Pstn
Document Number: 001-53516 Rev. **
Description
This bit sets the scan position.
Page 16 of 34
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PRELIMINARY
CY8C20111, CY8C20121
7.17 CS_FINGER_TH_x
Finger Threshold Registers
CS_FINGER_TH_0: 66h
1/2 Button
CS_FINGER_TH_1: 67h (Not available in 1 Button)
7
6
5
4
3
Access: FD
RW: 64
Bit Name
FT[7:0]
2
1
0
This register sets the finger threshold value for CapSense inputs. Possible values are 3 to 255. This parameter should be configured
individually for each CapSense inputs.
This register should be set after setting 0x07, 0x50, and 0x51 registers.
Bit
Name
[7:0]
FT [7:0]
Description
These bit set the finger threshold for CapSense inputs.
7.18 CS_IDAC_x
IDAC Setting Registers
CS_IDAC_0: 70h CS_IDAC_1: 71h (Not available in 1 Button)
1/2 Button
7
6
5
4
3
Access: FD
RW: 0A
Bit Name
IDAC[7:0]
2
1
0
The IDAC register controls the sensitivity of the CapSense algorithm. This register is used to tune the CapSense input for specific
design or overlays. Decreasing the value of this register increases the sensitivity of the CapSense buttons and vice versa. Decreasing
the value of IDAC increases noise and vice versa.
Possible values are 1 to 255. If the value is set to 0 then the value is reset to default value 10.
The recommended value is greater than 4. Setting value < 4 creates excessive amount of noise.
This register should be set after setting 0x07, 0x50, and 0x51 registers.
Bit
Name
[7:0]
Description
IDAC [7:0]
These bit set the IDAC values.
7.19 I2C_ADDR_LOCK
I2C Address Lock Registers
I2C_ADDR_LOCK: 79h
1/2 Button
7
6
5
4
3
2
Access: FD
1
0
WPR: 0
I2CAL
Bit Name
2
2
This register is used to unlock and lock the I C address register (7Ch) access. The device I C address should be modified by writing
new address to register 7Ch after unlocking the access using this register. Write to the 7C register during the locked state does not
have any effect and the new address take effect only after the access is locked.
To lock or unlock the I2C AL bit, the following three bytes must be written to register 79h:
■
unlock I2CAL: 3Ch A5h 69h
■
lock I2CAL: 96h 5Ah C3h
Reading the I2CAL bit from register 79h indicates the current access state.
Bit
Name
0
I2CAL
Document Number: 001-53516 Rev. **
Description
This bit gives the lock/unlock status of I2C address.
0
Unlocked
1
Locked
Page 17 of 34
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PRELIMINARY
CY8C20111, CY8C20121
7.20 DEVICE_ID
Device ID Register
DEVICE_ID: 7Ah
1 Button
Access: FD
Bit Name
2 Button
Access: FD
Bit Name
7
6
5
4
3
R: 11
DEV_ID[7:0]
2
1
0
7
6
5
4
2
1
0
3
R: 21
DEV_ID[7:0]
This register contains the device and product ID. The device and product ID corresponds to “xx” in CY8C201xx.
Bit
Name
7:0
DEV_ID [7:0]
Description
These bits contain the device and product ID.
Part No
CY8C20111
CY8C20121
Device/Product ID
11
21
7.21 DEVICE_STATUS
Device Status Register
DEVICE_STATUS: 7Bh
1/2 Button
7
6
Access: FD
R : 00
Bit Name
Ip_Volt[1:0]
5
R: 0
IRES
4
R:0
Load_FD
3
R: 0
No_NVM_Wr
2
1
R: 0
CSE
0
R: 0
DIGE
This register contains the device status.
Bit
Name
7:6
Ip_Volt [1:0]
Description
Supply voltage is automatically detected and these bits are set accordingly.
Ip_Volt[1:0]
00
01
10
11
5
IRES
4
Load_FD
3
No_NVM_Wr
1
CSE
0
DIGE
Document Number: 001-53516 Rev. **
Supply Voltage
5
3.3
2.7
Reserved
When set to ‘1’, this bit indicates that an internal reset occurred.
0
indicates the last system reset was not internal reset
1
indicates the last system reset was internal reset
This bit indicates whether factory defaults are loaded during power up.
0
User default configuration is loaded during power up
1
Factory default configuration is loaded during power up
When set to ‘1’, this bit indicates that the supply voltage applied to the device Is too
low for a write to nonvolatile memory operation, and no write is performed. This bit
must be checked before any Store or Write POR command.
This bit indicates whether CapSense function is enabled or disabled.
0
Functionality of CapSense block is disabled
1
Functionality of CapSense block is enabled
This bit indicates whether GP Output function is enabled or disabled.
0
Functionality of Digital output block is disabled
1
Functionality of Digital output block is enabled
Page 18 of 34
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PRELIMINARY
CY8C20111, CY8C20121
7.22 I2C_ADDR_DM
Device I2C Address and I2C Pin Drive Mode Register
I2C_ADDR_DM: 7Ch
1 Button
7
6
5
4
3
2
Access: FD
RW: 0
RW: 00
Bit Name
I2CIP_EN
I2C_ADDR[6:0]
1
0
This register sets the drive mode of I2C pins and I2C slave address. To write to this register, register 79h must first be unlocked. The
value written to register 7Ch is applied only after locking register 79h again.
Bit
Name
7
I2CIP_EN
6:0
I2C_ADDR [6:0]
Description
This bit is used to set the I2C pins drive mode.
0
Internal pull up enabled
1
Internal pull up disabled
Used to set the device I2C address.
7.23 CS_READ_BUTTON
Button Select Register
I2C_ADDR_DM: 81h
1 Button
7
6
5
4
3
2
1
0
Access: FD
RW: 0
RW: 0
Bit Name
RD_EN
CSBN[0]
2 Button
7
Access: FD
RW: 0
RW: 00
Bit Name
RD_EN
CSBN[1:0]
6
5
4
3
2
1
0
The scan result of a CapSense input (raw count, difference count, and baseline) can be read only for one input at a time using 82h-87h
registers. This register is used to select a CapSense input to read the raw count, difference count, and baseline. Only the pins defined
as CapSense inputs in register 07h can be used with this register. Trying to select other pins not defined as CapSense does not have
any change.
Bit
Name
7
RD_EN
1:0
CSBN [1:0]
Description
This bit enables the CapSense raw data reading.
0
Disable CapSense scan result reading
1
Enable CapSense scan result reading
These bits decide which CapSense button scan result are read. When writing to this
register, the bitmask must contain only one bit set to ’1’, otherwise the data is
discarded.
CSBN [1:0]
01
10
Document Number: 001-53516 Rev. **
CapSense Button No
1
2
Page 19 of 34
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PRELIMINARY
CY8C20111, CY8C20121
7.24 CS_READ_BLx
Baseline Value MSB/LSB Registers
CS_READ_BLM: 82h
1/2 Button
CS_READ_BLL: 83h
7
6
5
4
3
Access: FD
R: 00
Bit Name
BL [7:0]
2
1
0
1
0
Reading from this register returns the 2-byte current baseline value for the selected CapSense input.
Bit
Name
7:0
BL [7:0]
Description
These bits represent the baseline value.
7.25 CS_READ_DIFFx
Difference Count Value MSB/LSB Registers
CS_READ_DIFFM: 82h
1/2 Button
7
CS_READ_DIFFL: 83h
6
5
4
3
Access: FD
R: 00
Bit Name
DIF [7:0]
2
Reading from this register returns the 2-byte current difference count for the selected CapSense input.
Bit
Name
Description
7:0
DIF [7:0]
These bits represent the sensor difference count.
7.26 CS_READ_RAWx
Difference Count Value MSB/LSB Registers
CS_READ_RAWM: 82h
1/2 Button
7
CS_READ_RAWL: 83h
6
5
4
3
Access: FD
R: 00
Bit Name
RC [7:0]
2
1
0
Reading from this register returns the 2-byte current raw count value for the selected CapSense input.
Bit
Name
7:0
RC [7:0]
Document Number: 001-53516 Rev. **
Description
These bits represent the raw count value.
Page 20 of 34
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PRELIMINARY
CY8C20111, CY8C20121
7.27 CS_READ_STATUS
Sensor On Status Register
CS_READ_STATUS: 88h
1 Button
7
6
5
4
3
2
1
0
Access: FD
R: 0
Bit Name
BT_ST[0]
2 Button
7
6
5
4
3
2
1
0
Access: FD
R: 00
Bit Name
BT_ST[1:0]
This register gives the sensor ON/OFF status. A bit ‘1’ indicates sensor is ON and ‘0’ indicates sensor is OFF.
Bit
Name
Description
1:0
BT_ST [1:0]
These bits used to represent sensor status.
0
Sensor OFF
1
Sensor ON
7.28 COMMAND_REG
Command Register
COMMAND_REG: A0h
1/2 Button
7
6
5
4
3
Access: FD
W: 00
Bit Name
Cmnd [7:0]
2
1
0
Commands are executed by writing the command code to the command register.
Bit
Name
7:0
Cmnd [7:0]
Command
Code
Description
Refer to the following table for command register opcodes.
Name
Description
00h
Get Firmware Revision
The I2C buffer is loaded with the one byte firmware revision value. Reading one byte
after writing this command returns the firmware revision. The upper nibble of the
firmware revision byte is the major revision number and the lower nibble is the minor
revision number.
01h
Store Current Configuration to NVM
The current register settings are saved in nonvolatile memory (Flash). This setting is
automatically loaded after the next device reset/power up or if the Reconfigure Device
(06h) command is issued.
02h
Restore Factory
Configuration
Replaces the saved user configuration with the factory default configuration. Current
settings are unaffected by this command. New settings are loaded after the next device
reset/power up or if the 06h command is issued.
03h
Write POR Defaults
Sends new power up defaults to the CapSense controller without changing current
settings unless the 06h command is issued afterwards. This command is followed by
123 data bytes according to the POR Default Data Structure table. The CRC is calculated
as the XOR of the 122 data bytes (00h-79h). If the CRC check fails or an incomplete
block is sent, the slave responds with an ACK and the data is NOT saved to Flash.
To define new POR defaults:
Document Number: 001-53516 Rev. **
■
Write command 03h
■
Write 122 data bytes with new values of registers (use the _flash.iic file generated
from s/w tool)
■
Write one CRC byte calculated as XOR of previous 122 data bytes
Page 21 of 34
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PRELIMINARY
CY8C20111, CY8C20121
Command
Code
04h
05h
Name
Read POR Defaults
Read Device Configuration (RAM)
Description
Reads the POR settings stored in the nonvolatile memory. To read POR defaults:
■
Write command 04h
■
Read 122 data bytes
■
Read one CRC byte
Reads the current device configuration. Gives the user "flat-address-space" access to
all device settings. To read device configuration:
■
Write command 05h
■
Read 122 data bytes
■
Read one CRC byte
06h
Reconfigure Device
(POR)
Immediately reconfigures the device with actual POR defaults from Flash. Has the same
effect on the registers as a POR. This command can only be executed in setup operation
mode (command code 08).
07h
Set Normal Operation
Mode
Sets the device in normal operation mode. In this mode, CapSense pin assignments
cannot be modified; settling time, IDAC setting, external capacitor, and sensor
auto-reset also cannot be modified.
08h
Set Setup Operation
Mode
Sets the device in setup operation mode. In this mode, CapSense pin assignments can
be changed along with other parameters.
09h
Start CapSense
Scanning
Allows the user to start CSA scanning after it has been stopped using command 0x0A.
Note that at POR, scanning is enabled and started by default if one or more sensors are
enabled.
0Ah
Stop CapSense
Scanning
Allows the user to stop CSA scanning. A system host controller might initiate this
command before powering down the device to make sure that during power down no
CapSense touches are detected.
When CSA scanning is stopped by the user and the device is still in the valid VCC
operating range, the following behavior is supported:
0Bh
Returns CapSense
Scanning Status
Document Number: 001-53516 Rev. **
■
Any change to configuration can still be done (as long as VCC is in operating range).
■
Command code 0x06 overrides the status of stop/scan by enabling and starting CSA
scanning if one or more sensors are enabled.
■
CapSense read-back values return 0x00.
The I2C buffer is loaded with the one-byte CSA scanning status value. After writing the
value 0Bh to the A0h register, reading one byte returns the CSA scanning status. It
returns the LVD_STOP_SCAN and STOP_SCAN bits.
LVD_STOP_SCAN is bit 3 - Set when CSA is stopped because VCC is outside the valid
operating range. STOP_SCAN is bit 2 - Set when CSA is stopped by the user by writing
command 0x0A.
Page 22 of 34
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PRELIMINARY
CY8C20111, CY8C20121
8. Layout Guidelines and Best Practices
Sl.
No.
Category
Min
Max
Recommendations/Remarks
1
Button Shape
2
Button Size
5 mm
3
Button Button Spacing
= Button
Ground
Clearance
4
Button Ground Clearance
0.5 mm
5
Ground Flood - Top Layer
Hatched ground 7 mil trace and 45 mil grid (15% filling)
6
Ground Flood - Bottom Layer
Hatched ground 7 mil trace and 70 mil grid (10% filling)
7
Trace Length from Sensor to
PSoC - Buttons
8
Trace Width
9
Trace Routing
Traces should be routed on the non sensor side. If any non
CapSense trace crosses CapSense trace, ensure that intersection is orthogonal.
10
Via Position for the Sensors
Via should be placed near the edge of the button/slider to
reduce trace length thereby increasing sensitivity.
11
Via Hole Size for Sensor Traces
12
No. of Via on Sensor Trace
13
CapSense Series Resistor
Placement
14
Distance between any
CapSense Trace to Ground
Flood
15
Device Placement
Mount the device on the layer opposite to sensor. The
CapSense trace length between the device and sensors
should be minimum
16
Placement of Components in 2
Layer PCB
Top layer-sensor pads and bottom layer-PSoC, other components and traces.
17
Placement of Components in 4
Layer PCB
Top layer-sensor pads, second layer – CapSense traces,
third layer-hatched ground, bottom layer- PSoC, other
components and non CapSense traces
18
Overlay Thickness - Buttons
19
Overlay Material
Should to be non conductive material. Glass, ABS Plastic,
Formica
20
Overlay Adhesives
Adhesive should be non conductive and dielectrically homogenous. 467MP and 468MP adhesives made by 3M are
recommended.
21
LED Back Lighting
Cut a hole in the sensor pad and use rear mountable LEDs.
Refer Example PCB Layout Design with Two CapSense
Buttons and Two LEDs on page 26.
22
Board Thickness
Standard board thickness for CapSense FR4 based designs
is 1.6 mm.
Document Number: 001-53516 Rev. **
Solid round pattern, round with LED hole, rectangle with
round corners
0.17 mm
15 mm
10 mm
8 mm
2 mm
Button ground clearance = Overlay Thickness
200 mm
< 100 mm.
0.20 mm
0.17 mm (7 mil)
10 mil
1
10 mil
0 mm
2
1
10mm
Place CapSense series resistors close to PSoC for noise
suppression.CapSense resistors have highest priority place
them first.
20 mil
20 mil
2 mm
1 mm
Page 23 of 34
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PRELIMINARY
CY8C20111, CY8C20121
Figure 7. Button Shapes
Figure 8. Button Layout Design
X: Button to ground clearance
Y: Button to button clearance
Figure 9. Recommended Via-hole Placement
Document Number: 001-53516 Rev. **
Page 24 of 34
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PRELIMINARY
CY8C20111, CY8C20121
8.1 Example PCB Layout Design with Two CapSense Buttons and Two LEDs
Figure 10. Top Layer
Figure 11. Bottom Layer
Document Number: 001-53516 Rev. **
Page 25 of 34
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PRELIMINARY
CY8C20111, CY8C20121
9. Operating Voltages
For details on I2C 1x Ack time, refer Register Map on page 7 and CapSense Express Commands on page 8. I2C 4x Ack time is
approximately four times the values mentioned in these tables.
10. CapSense Constraints
Parameter
Min
Typ
Parasitic Capacitance (CP) of the
CapSense Sensor
Overlay Thickness
Supply Voltage Variation (VDD)
Document Number: 001-53516 Rev. **
0
1
Max
Units
30
pF
2
mm
Notes
All layout best practices followed, properly
tuned and noise free condition.
± 5%
Page 26 of 34
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PRELIMINARY
CY8C20111, CY8C20121
11. Electrical Specifications
11.1 Absolute Maximum Ratings
Parameter
Description
Min
Typ
Max
Unit
Notes
Higher storage temperatures reduce data
retention time. Recommended storage
temperature is +25°C ± 25°C (0°C to 50°C).
Extended duration storage temperatures
above 65°C degrade reliability
TSTG
Storage temperature
–55
25
+100
°C
TA
Ambient temperature with power
applied
–40
–
+85
°C
VDD
Supply voltage on VDD relative to VSS
–0.5
–
+6.0
V
VIO
DC input voltage
VSS – 0.5
–
VDD + 0.5
V
VIOZ
DC voltage applied to tri-state
VSS – 0.5
–
VDD + 0.5
V
IMIO
Maximum current into any GPIO pin
–25
–
+50
mA
ESD
Electro static discharge voltage
2000
–
–
V
LU
Latch up current
–
–
200
mA
Human body model ESD
11.2 Operating Temperature
Min
Typ
Max
Unit
TA
Parameter
Ambient temperature
Description
–40
–
+85
°C
TJ
Junction temperature
–40
–
+100
°C
Document Number: 001-53516 Rev. **
Notes
Page 27 of 34
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PRELIMINARY
CY8C20111, CY8C20121
11.3 DC Electrical Characteristics
11.3.1 DC Chip Level Specifications
Parameter
Description
Min
Typ
Max
Unit
VDD
Supply voltage
2.40
–
5.25
V
IDD
Supply current
–
1.5
2.5
mA
Notes
Conditions are VDD = 3.10V, TA = 25°C
11.3.2 5V and 3.3V DC General Purpose I/O Specifications
This table lists guaranteed maximum and minimum specifications for the voltage and temperature ranges: 4.75V to 5.25V and
-40°C<TA<85°C, 3.10V to 3.6V -40°C<TA<85°C. Typical parameters apply to 5V and 3.3V at 25°C and are for design guidance only.
Parameter
Description
Min
Typ
Max
Unit
–
–
V
VOH1
High output voltage
VDD – 0.2
Notes
IOH < 10 µA/pin, VDD > 3.10V
VOH2
High output voltage
VDD – 0.9
–
–
V
IOH = 1 mA/pin, VDD > 3.10V
VOL
Low output voltage
–
–
0.75
V
IOL = 20 mA/pin, VDD > 3.10V, maximum of
40 mA sink current
COUT
Capacitive load on pins as output
0.5
1.7
5
pF
Package and pin dependent.
Temp = 25°C.
11.3.3 2.7 DC General Purpose I/O Specifications
This table lists guaranteed maximum and minimum specifications for the voltage and temperature ranges: 2.4V to 2.90V and
-40°C<TA<85°C, respectively. Typical parameters apply to 2.7V at 25°C and are for design guidance only.
Min
Typ
Max
Unit
VOH1
Parameter
High output voltage
Description
VDD – 0.2
–
–
V
IOH < 10 µA/pin
Notes
VOH2
High output voltage
VDD – 0.5
–
–
V
IOH = 0.2 mA/pin
VOL
Low output voltage
–
–
0.75
V
IOL = 10 mA/pin, maximum of 20 mA sink
current
COUT
Capacitive load on pins as output
0.5
1.7
5
pF
Package and pin dependent.
Temp = 25°C.
11.3.4 2.7V DC Spec for I2C Line with 1.8V External Pull-Up
This table lists guaranteed maximum and minimum specifications for the voltage and temperature ranges: 2.4V to 2.9V and 3.10V to
3.60V, and -40°C<TA <85°C, respectively. Typical parameters apply to 2.7V at 25°C. The I2C lines drive mode must be set to open
drain and pulled up to 1.8V externally.
Parameter
Description
Min
Typ
Max
Unit
Notes
–
–
0.4
V
IOL=5 mA/pin, maximum of 10 mA device
sink current
2.4<VDD <2.9V and 3.1<VDD <3.6V.
VOLP
Low output voltage
VIL
Input low voltage
–
–
0.75
V
VDD = 2.4 to 2.90V and 3.10V to 3.6V.
VIH
Input high voltage
1.4
–
–
V
VDD = 2.4 to 2.7V.
0.5
1.7
5
pF
Package and pin dependent.
Temp = 25°C.
4
5.6
8
kΩ
Min
Typ
Max
Unit
–
–
2.36
2.60
2.40
2.65
V
V
2
CI2C
Capacitive load on I C pins
RPU
Pull up resistor
11.3.5 DC POR and LVD Specifications
Parameter
VPPOR0
VPPOR1
Description
VDD Value for PPOR Trip
VDD= 2.7V
VDD= 3.3V, 5V
Document Number: 001-53516 Rev. **
Notes
VDD must be greater than or equal to 2.5V
during startup or reset from watchdog.
Page 28 of 34
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PRELIMINARY
CY8C20111, CY8C20121
11.3.6 DC Flash Write Specifications
This table lists guaranteed maximum and minimum specifications for the voltage and temperature ranges: 4.75V to 5.25V and
-40°C<TA<85°C, 3.10V to 3.6V and -40°C<TA<85°C or 2.4V to 2.90V and -40°C<TA<85°C, respectively. Typical parameters apply to
5V, 3.3V, or 2.7V at 25°C. These are for design guidance only. Flash Endurance and Retention specifications are valid only within the
range: 25°C±20°C during the Flash Write operation. It is at the user’s own risk to operate out of this temperature range. If Flash writing
is done out of this temperature range, the endurance and data retention reduces.
Symbol
VddIWRITE
IDDP
FlashENPB
FlashDR
Description
Supply Voltage for Flash Write Operations[6]
Supply Current for Flash Write Operations
Flash Endurance
Flash Data Retention
Min
2.7
–
50,000
10
Typ
–
5
–
–
Max
–
25
–
–
Units
V
mA
–
Years
Notes
Erase/write cycles
11.4 CapSense Electrical Characteristics
Max (V)
Typ (V)
Min (V)
Conditions for Supply Voltage
Result
3.6
3.3
3.1
<2.9
The device automatically reconfigures itself to work in 2.7V
mode of operation.
>2.9 or <3.10
2.90
5.25
2.7
5.0
2.45
4.75
This range is not recommended for CapSense usage.
<2.45V
The scanning for CapSense parameters shuts down until
the voltage returns to over 2.45V.
>3.10
The device automatically reconfigures itself to work in 3.3V
mode of operation.
<2.4V
The device goes into reset.
<4.73V
The scanning for CapSense parameters shuts down until
the voltage returns to over 4.73V.
Note
7. Commands involving Flash Writes (0x01, 0x02, 0x03) must be executed only within the same VCC voltage range detected at POR (power on, or command 0x06) and
above 2.7V.
Document Number: 001-53516 Rev. **
Page 29 of 34
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PRELIMINARY
CY8C20111, CY8C20121
11.5 AC Electrical Specifications
11.5.1 5V and 3.3V AC General Purpose I/O Specifications
Parameter
Description
Min
Max
Unit
Notes
TRise
Rise time, strong mode,
Cload = 50 pF
15
80
ns
VDD = 3.10V to 3.6V and 4.75V to
5.25V, 10% - 90%
TFall
Fall time, strong mode,
Cload = 50 pF
10
50
ns
VDD = 3.10V to 3.6V and 4.75V to
5.25V, 10% - 90%
Min
Max
Unit
11.5.2 2.7V AC General Purpose I/O Specifications
Parameter
Description
Notes
TRise
Rise time, strong mode,
Cload = 50 pF
15
100
ns
VDD = 2.4V to 2.90V, 10% - 90%
TFall
Fall time, strong mode,
Cload = 50 pF
10
70
ns
VDD = 2.4V to 2.90V, 10% - 90%
11.5.3 AC I2C Specifications
Parameter
FSCLI2C
Description
SCL clock frequency
THDSTAI2C Hold time (repeated) START condition. After
this period, the first clock pulse is generated
Standard
Mode
Fast Mode
Min
Max
Min
Max
0
100
0
400
kbps
4.0
–
0.6
–
µs
Units
TLOWI2C
LOW period of the SCL clock
4.7
–
1.3
–
µs
THIGHI2C
HIGH period of the SCL clock
4.0
–
0.6
–
µs
TSUSTAI2C Setup time for a repeated START condition
4.7
–
0.6
–
µs
2
0
–
0
–
µs
2
TSUDATI C Data setup time
250
–
100
–
ns
TSUSTOI2C Setup time for STOP condition
4.0
–
0.6
–
µs
TBUFI2C
BUS free time between a STOP and START
condition
4.7
–
1.3
–
µs
TSPI2C
Pulse width of spikes suppressed by the
input filter
–
–
0
50
ns
THDDATI C Data hold time
Notes
Fast mode not supported for
VDD < 3.0V
~
~
~
~
Figure 12. Definition of Timing for Fast/Standard Mode on the I2C Bus
tf
tLOWI2C
tr
tSUDATI2C
~
~
tf
~
~
SDA
tHDSTAI2C
tSPI2C
tBUFI2C
tr
S
tHDDATI2C
Document Number: 001-53516 Rev. **
tHIGHI2C
tSUSTAI2C
~
~
tHDSTAI2C
~
~
SCL
Sr
tSUSTOI2C
P
S
Page 30 of 34
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PRELIMINARY
CY8C20111, CY8C20121
12. Examples of Frequently Used I2C Commands
Sl. No.
I2C Commands[7]
Requirement
Comment
1
Enter into setup mode
W 00 A0 08
2
Enter into normal mode
W 00 A0 07
3
Load factory defaults to RAM
registers
W 00 A0 02
4
Do a software reset
W 00 A0 08
W 00 A0 06
5
Save current configuration to flash
W 00 A0 01
6
Load factory defaults to RAM
registers and save as user configuration
W
W
W
W
7
Disable combinational logic output
to DIG0
W 00 1C 00
8
Disable combinational logic output
to DIG1
W 00 21 00
9
Clearing (logic 0) the both DIG0
and DIG1 outputs
W 00 04 00
10
Setting (logic 1) the DIG0 and
clearing (Logic 0) the DIG1 outputs
W 00 04 01
11
Clearing (logic 0) the DIG0 and
Setting (Logic 1) the DIG1 outputs
W 00 04 02
12
Setting (logic 1) the both DIG0 and
DIG1 outputs
W 00 04 03
13
Change CapSense clock to IMO/2
W 00 A0 08
W 00 51 20
W 00 A0 07
; Enter into setup mode
; CapSense clock is set as IMO/2
; Enter into normal mode
14
Change value of IDAC0 to ‘x’h
W 00 70 x
‘x’ represents new value of IDAC register
15
Change value of IDAC1 to ‘y’h
W 00 71 y
‘y’ represents new value of IDAC register
16
Change value of IDAC0 and IDAC1
to ‘x’h and ‘y’h
W 00 70 x y
‘x’ and ‘y’ represents new value of IDAC register
17
Change the value FT0 to ‘x’h
W 00 66 x
‘x’ represents new value of FT register
18
Change the value FT1 to ‘y’h
W 00 67 y
‘y’ represents new value of FT register
19
Change the value FT0 and FT1 to
‘x’h and ‘y’h
W 00 66 x y
‘x’ and ‘y’ represents new value of FT registers
20
Change noise threshold to ‘x’h
W 00 4E x
21
Read CapSense button CS0 scan
results
W 00 81 81
W 00 82
R 00 RD RD RD RD
RD RD
; Select CapSense button for reading scan result
; Set the read point to 82h
; Consecutive 6 reads gets baseline, difference count
and raw count (all two byte each)
22
Read CapSense button status
register
W 00 88
R 00 RD
; Set the read pointer to 88
; Reading a byte gets status CapSense inputs
00 A0 08
00 A0 02
00 A0 01
00 A0 06
; Enter into setup mode
; Do software reset
; Enter into setup mode
; Load factory defaults to SRAM
; Save the configuration to Flash. Wait for time specified
in Table 6.
; Do software reset
Combinational logic output on DIG0 and DIG1 should
be disabled before dong this operation (SL# 7 and 8)
Note
8. The ‘W’ indicates the write transfer and the next byte of data represents the 7-bit I2C address. The I2C address is assumed to be ‘0’ in the above examples.
Similarly ‘R’ indicates the read transfer followed by 7-bit address and data byte read operations.
Document Number: 001-53516 Rev. **
Page 31 of 34
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PRELIMINARY
CY8C20111, CY8C20121
13. Ordering Information
Ordering Code
Package
Diagram
Package Type
Operating
Temperature
CapSense
Blocks
CapSense
Inputs
Digital
Outputs
XRES
Pin
CY8C20111-SX1I
51-85066
8 SOIC
Industrial
Yes
1
1
No
CY8C20111-SX1IT
51-85066
8 SOIC (Tape and Reel)
Industrial
Yes
1
1
No
CY8C20121-SX1I
51-85066
8 SOIC
Industrial
Yes
2
2
No
CY8C20121-SX1IT
51-85066
8 SOIC (Tape and Reel)
Industrial
Yes
2
2
No
Note For Die sales information, contact a local Cypress sales office or Field Applications Engineer (FAE).
13.1 Ordering Code Information
CY 8 C 201 xx
- SX 1 I T
Tape and Reel
Thermal Rating : Industrial
8 pin pinout
Package Type : SOIC Pb- Free
Part Number
Family Code
Technology Code: C = CMOS
Marketing Code: 8 = Cypress Semiconductors
Company ID: CY = Cypress
Document Number: 001-53516 Rev. **
Page 32 of 34
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PRELIMINARY
CY8C20111, CY8C20121
14. Package Diagram
Figure 13. 8-Pin (150-Mil) SOIC (51-85066)
8 Lead (150 Mil) SOIC - S08
PIN 1 ID
4
1
1. DIMENSIONS IN INCHES[MM] MIN.
MAX.
2. PIN 1 ID IS OPTIONAL,
ROUND ON SINGLE LEADFRAME
RECTANGULAR ON MATRIX LEADFRAME
0.150[3.810]
0.157[3.987]
3. REFERENCE JEDEC MS-012
0.230[5.842]
0.244[6.197]
4. PACKAGE WEIGHT 0.07gms
PART #
S08.15 STANDARD PKG.
5
SZ08.15 LEAD FREE PKG.
8
0.189[4.800]
0.196[4.978]
0.010[0.254]
0.016[0.406]
SEATING PLANE
X 45°
0.061[1.549]
0.068[1.727]
0.004[0.102]
0.050[1.270]
BSC
0.004[0.102]
0.0098[0.249]
0°~8°
0.016[0.406]
0.035[0.889]
0.0075[0.190]
0.0098[0.249]
0.0138[0.350]
0.0192[0.487]
51-85066-*C
Document Number: 001-53516 Rev. **
Page 33 of 34
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PRELIMINARY
CY8C20111, CY8C20121
15. Document History Page
Document Title: CY8C20111, CY8C20121 CapSense Express™ - One Button and Two Button Capacitive Controllers
Document Number: 001-53516
Rev.
ECN.
Orig. of
Change
Submission
Date
**
2709248
SLAN/PYRS
See ECN
Description of Change
New data sheet
16. Sales, Solutions, and Legal Information
16.1 Worldwide Sales and Design Support
Cypress maintains a worldwide network of offices, solution centers, manufacturer’s representatives, and distributors. To find the office
closest to you, visit us at cypress.com/sales.
16.2 Products
PSoC
psoc.cypress.com
Clocks & Buffers
clocks.cypress.com
Wireless
wireless.cypress.com
Memories
memory.cypress.com
Image Sensors
image.cypress.com
© Cypress Semiconductor Corporation, 2009. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use of any
circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be used for medical,
life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its products for use as critical
components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress products in life-support systems
application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Any Source Code (software and/or firmware) is owned by Cypress Semiconductor Corporation (Cypress) and is protected by and subject to worldwide patent protection (United States and foreign),
United States copyright laws and international treaty provisions. Cypress hereby grants to licensee a personal, non-exclusive, non-transferable license to copy, use, modify, create derivative works of,
and compile the Cypress Source Code and derivative works for the sole purpose of creating custom software and or firmware in support of licensee product to be used only in conjunction with a Cypress
integrated circuit as specified in the applicable agreement. Any reproduction, modification, translation, compilation, or representation of this Source Code except as specified above is prohibited without
the express written permission of Cypress.
Disclaimer: CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Cypress reserves the right to make changes without further notice to the materials described herein. Cypress does not
assume any liability arising out of the application or use of any product or circuit described herein. Cypress does not authorize its products for use as critical components in life-support systems where
a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application implies that the manufacturer
assumes all risk of such use and in doing so indemnifies Cypress against all charges.
Use may be limited by and subject to the applicable Cypress software license agreement.
Document Number: 001-53516 Rev. **
Revised May 20, 2009
Page 34 of 34
CapSense Express™, PSoC Designer™, and Programmable System-on-Chip™ are trademarks and PSoC® is a registered trademark of Cypress Semiconductor Corp. All other trademarks or registered
trademarks referenced herein are property of the respective corporations. Purchase of I2C components from Cypress or one of its sublicensed Associated Companies conveys a license under the
Philips I2C Patent Rights to use these components in an I2C system, provided that the system conforms to the I2C Standard Specification as defined by Philips. All products and company names
mentioned in this document may be the trademarks of their respective holders.
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