STMPE812ABJR STMicroelectronics, STMPE812ABJR Datasheet
STMPE812ABJR
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STMPE812ABJR Summary of contents
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... Portable media players ■ Game consoles ■ Mobile and smart phones Table 1. Device summary Order code STMPE812ABJR July 2011 Touchscreen controller S-Touch with PWM and dedicated RESET pin A Description The STMPE812A is a 4-wire resistive touchscreen controller with 4-bit port expander integrated. ...
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Contents Contents 1 STMPE812A functional overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1 Pin ...
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STMPE812A 12 GPIO port controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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STMPE812A functional overview 1 STMPE812A functional overview The STMPE812A consists of the following blocks: 2 ● interface ● GPIO/PWM controller ● Touchscreen controller (TSC) ● Analog-to-digital converted (ADC) ● Driver and switch control unit Figure 1. STMPE812A block ...
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STMPE812A 1.1 Pin configuration and functions Figure 2. Pin configuration (top through view) Table 2. Pin assignments Pin Name RESETN D2 GND D1 SCL Current capacity 50 mA current limit ...
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STMPE812A functional overview Table 2. Pin assignments (continued) Pin Name C1 SDA Note: All I/O operates HBM ESD on all touchscreen pins (+/- ...
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STMPE812A 1.2 Typical application Figure 3. Typical application STMPE812A functional overview Doc ID 18225 Rev 4 7/53 ...
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I2C interface interface For the bus master to communicate to the slave device, the bus master must initiate a Start condition and be followed by the slave device address. Accompanying the slave device address, there is ...
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STMPE812A 2 2 features The features that are supported by the I 2 ● slave device ● Operates at V ● Compliant to Philips I ● Supports standard (up to 100 Kbps) and fast (up to ...
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I2C interface Table 5. Operating modes Mode Read Write 10/53 Byte Programming sequence Start, Device address, R Register address to be read Restart, Device address, R Data Read, Stop If no Stop is issued, the Data ...
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STMPE812A Figure 5. Read and write modes (random and sequential) One byte Read More than one byte Read One byte Write More than one byte Read Device Reg Device Address Address Address Reg Device Device Address Address Address Data Device ...
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I2C interface 2.3 Read operation A write is first performed to load the register address into the Address Counter but without sending a Stop condition. Then, the bus master sends a reStart condition and repeats the Device Address with the ...
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STMPE812A 3 Power supply The STMPE812A GPIO operates from a supply pin V immunity, V above 2 recommended. CC Power up reset The STMPE812A is equipped with an internal POR circuit that holds the device in reset state, ...
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Charge pump 4 Charge pump The STMPE812A is integrated with an internal charge-pump. The charge pump is required for any ADC/TSC operations when V Activating the charge pump when V device. 14/53 is less than 2 > 2.5 ...
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STMPE812A 5 Power modes The STMPE812A operates states: active and hibernate. Active: – Whenever PEN-DOWN is detected, the device remains in active mode – Whenever PWM is active, the device remains in active mode – Whenever ADC ...
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Power modes Figure 6. Power modes state diagram STMPE812A is in active mode if PWM is running On power up reset, device goes to active state. However, as all the functional blocks are clocked off by default, no touch/hotkey activity ...
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STMPE812A 6 STMPE812A registers This section lists and describes the registers of the STMPE812A device, starting with a register map and then provides detailed descriptions of register types. Table 7. Register summary map table Address Register name Registers from 0x00 ...
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STMPE812A registers Table 7. Register summary map table (continued) Address Register name 0x44 Registers from 0x50 - 0x5F are accessible only if “PWM_OFF” bit in SYS_CTRL is set to “0”. PWM_CLOCK_ 0x50 0x51 6.1 Auto-increment/non auto-increment address The STMPE812A supports ...
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STMPE812A 7 System and identification registers Table 8. System and identification registers map Address 0x00 - 01 CHIP_ID 0x02 ID_VER 0x03 SYS_CTRL 0x04 PORT_FUNCTION 0x06 - 07 SCRATCH_PAD SYS_CTRL 7 6 RESERVED SOFT_RESET TSC_EN 0 0 Address: 0x03 Type: R/W ...
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System and identification registers PORT_FUNCTION PORT 2 FUNCTION RESERVED Address: 0x04 Type: R/W Reset: 0xF8 Description: Port function control register. [7:6] PORT 2 FUNCTION [5:4] RESERVED [3:2] PORT 1 FUNCTION [1:0] PORT 0 FUNCTION ...
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STMPE812A 8 Interrupt system The STMPE812A uses a 2-tier interrupt structure. In normal mode, interrupts from the GPIO and touchscreen controller assert the INT pin and are available in the Interrupt Status register (ISR). In pen down mode, the INT ...
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Interrupt system INT_CTRL INT_MODE RESERVED 0 Address: 0x08 Type: R/W Reset: 0x00 Description: This register is used to enable the interruption from a system related interrupt source to the host. [7] INT_MODE: ‘0’ for Pen-Down INT mode ...
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STMPE812A INT_EN TSC_ERR TSC_RELEASE Address: 0x09 Type: R/W Reset: 0x00 Description: This register is used to enable the interruption from a system related interrupt source to the host. [7] TSC_ERR Error encountered in ...
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Interrupt system ISR 7 6 TSC_ERR TSC_RELEASE 0 0 Address: 0x0A Type: R Reset: 0x00 Description: ISR register monitors the status of the interruption from a particular interrupt source to the host. Regardless whether the INT_EN bits are enabled, the ...
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STMPE812A 9 ADC controller A 12-bit ADC is integrated in the STMPE812A. The ADC could be used as generic analog- digital converter touchscreen controller capable of controlling a 4-wire resistive touchscreen. The ADC works ONLY with internal reference ...
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ADC controller ADC control register ADC_MODE ADC_CAP ADC_FREQ Address: 0x20 Type: R/W Reset: 0x33 Description: This register is used to configure the ADC operations. [7] ADC_MODE: ADC capture mode ‘0’ – Continuous capture according ...
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STMPE812A ADC data ADC_DATA_7 ADC_DATA_6 ADC_DATA_5 ADC_DATA_4 ADC_DATA_3 Address: 0x21-0x22 Type: R Reset: 0x0000 Address: ADC data register. [7:0] ADC_DATAx 2 Note: When the I C master accesses the data register, upper/lower byte consistency ...
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PWM controller 10 PWM controller The PWM allows the brightness control of a LED/motor driver. The PWM uses base clock that is ½ of the OSC frequency (typically 600 kHz). The base clock is divided by a programmable DIV[4:0], which ...
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STMPE812A PWM control1 register Brightness 0 Address: 0x51 Type: R/W Reset: 0x00 Description: PWM control1 register. [7:4] This defines the of the PWM channel output which in turn determines the brightness level of the LED that the ...
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PWM controller 10.2 Interrupt of PWM controller When non-infinite sequence is used, the completion of the PWM sequence causes the P0 bit in interrupt status register to be asserted. 30/53 Doc ID 18225 Rev 4 STMPE812A ...
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STMPE812A 11 Touchscreen controller The STMPE812A is integrated with a hard-wired touchscreen controller for 4-wire resistive type touchscreen. The touchscreen controller is able to operate completely autonomously, and would interrupt the connected CPU only when pre-defined event occurs. The TSC ...
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Touchscreen controller 11.1 Touchscreen controller detection sequence Following is the sequence of detection in the STMPE812A touchscreen controller for X, Y and Z: 1. Touch detect 2. Drive Y 3. Wait for settling time 4. Measure Y 5. Stop drive ...
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STMPE812A 11.3 Touchscreen controller registers Table 12. Touchscreen controller registers Address Register name 0x40 TSC_CTRL 0x41 TSC_DET_CFG1 0x42 TSC_DET_CFG2 TSC_SAMPLING 0x43 0x44 TSC_DATA Bit Type 8 R/W 8 R/W 8 R/W 8 R/W _RATE 8 R Doc ID 18225 Rev ...
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Touchscreen controller TSC CTRL MAV_MODE[2:0] 0 Address: 0x40 Type: R/W Reset: 0x00 Description: Touchscreen control register. [7:5] MAV_MODE[2:0] ‘000’ – MAV filter disabled ‘001’ – 6 remove 2 ‘010’ – 8 remove 4 ‘011’ – 10 remove ...
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STMPE812A TSC detect config PenStrength[1: Address: 0x41 Type: R/W Reset: 0xA4 Description: Touchscreen controller detection configuration 1 register. [7:6] PenStrength[1:0] Pen detect strength threshold ‘00’ – least sensitive (50 K pull-up) ‘01’ – sensitive ...
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Touchscreen controller TSC_DET_CFG2 Acq_Mode StatusRead Address: 0x42 Type: R/W Reset: 0xB0 Description: Touchscreen controller detection configuration 2 register. [7:6] Acq_Mode ‘00’ – Data acquisition timed by internal timer ‘01’ – Data acquisition triggered by ...
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STMPE812A TSC sampling rate Address: 0x43 Type: R/W Reset: 0x0A Description: Touchscreen controller sampling rate control register. [7:0] Sampling[7:0] Sets the sampling rate of touchscreen controller. Sampling Time = (sampling[7:0]+ Clock cycle ...
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Touchscreen controller Table 13. Touchscreen controller data register TSCDetectConfig2 OpMode StatusRead Data Valid Status Byte Structure 7 6 [7:2] RESERVED [1] DATA VALID 1: Touch data available/valid 0: Touch data not available/not valid Bit reset upon ...
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STMPE812A 11.4 Programming model Below are steps to configure the Touchscreen controller in 3 different acquisition modes. A. Autonomous touchscreen controller, 100 Hz, lowest power possible 1. Initialize the touchscreen controller (choose ACQ_Mode ‘00’ - data acquisition timed by internal ...
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Touchscreen controller The STMPE812A samples a new data set immediately after every complete read. If the host does not complete a data-set read, no further samples are taken. For each data point (4 bytes), number of I2C transaction required is: ...
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STMPE812A 12 GPIO port controller A total of 3 configurable ports are available in the STMPE812A port expander device. If configured as GPIO input/output, they are controlled by the GPIO registers. Table 14. GPIO registers Address 0x10 0x11 0x12 0x13 ...
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Electrical specification 13 Electrical specification Table 16. Absolute maximum rating Symbol V Supply voltage CC Vi-i2c Input voltage at SDA/SCL Vi-io Input voltage at P0-P5 On all touchscreen and GPIO pins (HBM) ESD On all other pins (HBM) Table 17. ...
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STMPE812A Table 18. Power consumption (T Symbol I max Operating current CC I max Operating current Suspend current suspend *operating current excludes current driving the touchscreen. (- All GPIO complies to JEDEC standard JESD-8-7) ...
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Electrical specification 13.2 AC electrical characteristics Table 20. AC electrical characteristics (-40 ° °C) Symbol Max maximum SCLK ClkI2C Minimum RESET pulse T RESET width Minimum INPUT width T required for GPIO state IN transition ...
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STMPE812A Table 22. Switch drivers specification (continued) (continued) Parameter ON resistance X resistance X resistance X resistance X resistance X resistance X-, Y- Drive current ( limit) Drive ...
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Package mechanical section 14 Package mechanical section In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available ...
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STMPE812A Table 23. CSP 12 (2.17 x 1.67 mm) mechanical data Symbol ccc $ Millimeters Min Typ 0.585 0.650 0.21 0.25 – 0.35 0.265 0.315 2.12 2.17 – ...
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Package mechanical section Figure 10. Footprint recommendation Figure 11. Tape information 48/53 Doc ID 18225 Rev 4 STMPE812A ...
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STMPE812A Table 24. Tape specifications Symbol 10Po Figure 12. Tape orientation 1. Pin top left corner based on above tape orientation. Min 1.78 2.34 0.68 3.45 ...
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Package mechanical section Figure 13. Device marking Figure 14. Reel drawing (front) 50/53 Doc ID 18225 Rev 4 STMPE812A ...
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STMPE812A Figure 15. Reel drawing (back) Table 25. Tape width (millimeters) Tape width max min max 180 60 8,4 Doc ID 18225 Rev 4 Package mechanical section W2 W3 max min max 14.4 7.9 10.9 51/53 ...
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Revision history 15 Revision history Table 26. Document revision history Date 18-Nov-2010 09-Mar-2011 23-May-2011 14-Jul-2011 52/53 Revision 1 Initial release. Document status promoted from preliminary data to datatasheet. 2 Updated Table 2. Updated: Footprint recommendation in 3 Replaced: Flip-chip 12 ...
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... STMPE812A Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...