STMPE812ABJR STMicroelectronics, STMPE812ABJR Datasheet - Page 26

• Manufacturer Part Number: STMPE812ABJR
• Description: Touch Screen Converters & Controllers Touchscreen cntrlr S-Touch
• Manufacturer: STMicroelectronics
• Type: Resistive Touch Controllersr

Specifications of STMPE812ABJR

• Rohs: yes
• Input Type: 1 TSC
• Data Rate: 400 kbps
• Resolution: 12 bit
• Interface Type: 4-wire, I2C
• Supply Voltage: 1.65 V to 3.6 V
• Supply Current: 100 uA
• Operating Temperature: - 40 C to + 85 C
• Package / Case: CSP-12
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Supply Voltage - Max: 3.6 V
• Supply Voltage - Min: 1.65 V

ADC controller
ADC control register
Address:
Type:
Reset:
Description:
26/53
ADC_MODE
7
0
ADC_CAP
[5:4] ADC_FREQ: ADC sampling frequency based on 1MHz RC (minimum 880 KHz)
[2:1] CP_Lock[1:0]: Only effective if CP_Arm is set to ‘1’.
[7] ADC_MODE: ADC capture mode
[6] ADC_CAP: ADC channel data capture
[3] CP_Arm: Writing ‘1’ arms the charge-pump for unlocking
[0] RESERVED
6
0
0x20
R/W
0x33
This register is used to configure the ADC operations.
‘0’ – Continuous capture according to sampling rate specified by ADC_FREQ register. New
data over-writes old data in ADC_DATA register.
‘1’ – One-shot capture. One sample is taken every time system writes ‘1’ to ADC_CAP bit
In one-shot mode:
Write ‘1’ to initiate data acquisition for the corresponding channel. Writing ‘0’ has no effect.
Reads ‘1’ if conversion is in progress.Reads ‘0’ if conversion is completed.
One-shot mode ADC generates interrupt in corresponding interrupt status bit on completion of
conversion
In continuous capture mode:
Write ‘1’ to initiate data acquisition for the corresponding channel. Writing ‘0’ to stop capturing.
00 – 10 K samples/sec
01 – 12.5 K samples/sec
10 – 15 K samples/sec
11 – 20 K samples/sec
NOTE: As the ADC is also used for TSC operation. This setting affects the maximum sampling
rate possible with TSC.
Writing ‘0’ un-arms it
Charge-pump is required for ADC/TSC operation when V
charge pump when V
device.
Charge-pump can be activated by unlocking CP_Lock after it is armed.
Always reads ‘00’.
Writing ‘01’ when CP_Arm is ‘1’ activates the charge pump.
Writing ‘00’, ‘10’ and ‘11’ does NOT activate the charge-pump, and clears the CP_Arm bit.
CP_Arm MUST BE set before writing to CP_Lock. Accesses to CP_Lock will be ignored, if
CP_Arm is ‘0’.
Note: CP_Arm and CP_Lock CANNOT be accessed in a single I
first ARM the CP with 1 I
if charge pump is activated
CP_LOCK reads “01” if charge pump is not activated
5
1
ADC_FREQ
4
1
CC
is more than 2.5 V may result in permanent damage of the
Doc ID 18225 Rev 4
CP_ARM
2
C transaction, and unlocks it in the next. CP_LOCK reads “00”
3
0
2
0
CP_Lock[1:0]
CC
is less than 2.5 V. Activating the
2
C transaction. System must
1
1
ADC control
STMPE812A
RESERVED
0
1