sx8652 Semtech Corporation, sx8652 Datasheet

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... HBM and Contact Discharge, and eliminates the need for external protection devices. The SX8652 is controlled by a high speed SPI™ serial interface. The SX8652 is available 3.0 mm 14-DFN package and a 1 2.0 mm wafer level chip scale package (WLCSP) for space conscience applications. ...

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... Coordinates Measurement............................................................................................................................. 16 5.3. Pen Detection ................................................................................................................................................ 17 6. Data Processing .................................................................................................................................................... 17 6.1. Host Interface and Control ............................................................................................................................. 17 6.1.1. SPI Read/Write Registers ....................................................................................................................... 18 6.1.2. SPI Reading Channel Data ..................................................................................................................... 18 6.1.3. Multiple Read/Write ................................................................................................................................. 18 6.1.4. SPI Host Commands............................................................................................................................... 19 6.1.5. Invalid Qualified Data .............................................................................................................................. 20 6.2. Register Map................................................................................................................................................. 21 6.3. Host Control Writing ...................................................................................................................................... 22 Revision V1.6/July 2010 ©2010 Semtech Corp. Page 2 SX8652 DATASHEET Page www.semtech.com ...

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... Acquisition Setup ........................................................................................................................................... 27 8.2. Channel Selection.......................................................................................................................................... 27 8.3. Noise Reduction............................................................................................................................................. 27 8.3.1. POWDLY................................................................................................................................................. 27 8.3.2. SETDLY .................................................................................................................................................. 28 8.3.3. AUX Input ................................................................................................................................................ 28 8.4. Interrupt Generation....................................................................................................................................... 28 8.5. Coordinate Throughput Rate ......................................................................................................................... 28 8.5.1. SPI Communication Time ....................................................................................................................... 28 8.5.2. Conversion Time ..................................................................................................................................... 29 8.5.3. AUTO MODE .......................................................................................................................................... 29 8.6. ESD event...................................................................................................................................................... 29 9. Packaging Information ........................................................................................................................................... 30 9.1. DFN Package................................................................................................................................................. 30 9.2. WLCSP Package ........................................................................................................................................... 31 Revision V1.6/July 2010 ©2010 Semtech Corp. Page 3 SX8652 DATASHEET Page www.semtech.com ...

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... DIN 2 NIRQ DOUT AUX/WIPER # Figure 2. SX8652 WLCSP Top View, Solder Bumps on Bottom Side YYWW: date code XXXXX: Lot Number Revision V1.6/July 2010 ©2010 Semtech Corp. 15kV ESD Low Power 4-Wire / 5-Wire Resistive Touchscreen Controller with SPI Interface PIN 1 14 ...

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... Digital Input 13 - NRST Digital Input 14 - (NC GND Power input 1.4. Simplified Block Diagram The SX8652 simplified block diagram is shown in Figure 3. VDD AUX/WIPER X+/BR To the touch Y+/TR screen X-/TL Y-/BL Figure 3. Simplified block diagram of the SX8652 Revision V1.6/July 2010 ©2010 Semtech Corp. 15kV ESD Low Power 4-Wire / 5-Wire Resistive ...

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... High ESD pins: X+/BR, X-/TL, ESD Y+/TR, Y-/BL, Aux/Wiper All pins except high ESD pins ESD High ESD pins: X+/BR, X-/TL, ESD Y+/TR, Y-/BL, Aux/Wiper Table 2. Absolute Maximum Ratings Symbol Table 3. Recommended Operating Conditions Symbol (iii) (iii) Table 4. Thermal Characteristics Page 6 SX8652 DATASHEET Min. Max. -0.5 3.9 DDABS V -0.5 3 125 ...

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... Converter stopped, pen detection off, SPI listening, OSC on, timer on VDD > 2V VDD < >-2mA OH I <2mA OL CMOS input ,C X-/ Y+/TR Y-/BL, C NIRQ ,C , NCS DIN C SCLK Table 5. Electrical Specifications Page 7 SX8652 DATASHEET Min. Typ Max Unit 105 140 uA 0.8V V +0.2 V ...

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... NIRQ At full scale Touch Pad Biasing Resistance PNDT PNDT PNDT PNDT recommendations Type 0402, tolerance +/-50% Table 5. Electrical Specifications Page 8 SX8652 DATASHEET Min. Typ Max Unit bits ±1 LSB 0.5 LSB ±1 LSB ±1.5 LSB 5 Ohm ...

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... DOD T CSI T CCZ T CSW Table 6. Host Interface Specifications , V ) defined in Table 6 unless otherwise mentioned tCKL tCKH tDH D11 Figure 4. SPI Timing Waveform Page 9 SX8652 DATASHEET Min Typ Max 5000 100 150 tCSW 50%VDD tDOD tCSI ...

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... As shown in Figure 5 with a 4-wire panel, the touch screen coordinates and touch pressure are converted into SPI format by the SX8652 for transfer to the host. The auxiliary input can be used to convert with 12-bit resolution any analog input in the supply range. It can also serves as an external synchronisation input to trig the touchscreen acquisition as described in the Application Information section ...

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... Figure 7. Simplified diagram of touchscreen pins 3.2.2. AUX/WIPER VDD AUX Figure 8. Simplified diagram of AUX/WIPER pin 3.3. Host Interface and Control Pins The SX8652 host and control interface consists of the SPI interface with NIRQ and NRST. 3.3.1. NIRQ HOST VDD NIRQ Figure 9. Simplified diagram of NIRQ Revision V1.6/July 2010 © ...

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... Figure 11 shows a simplified diagram of the VDD pin. Power Page 12 SX8652 DATASHEET The NRST pin is an active low input that provides a hardware reset of the SX8652's control circuitry. The NRST pin is protected to GROUND and have an internal pull-up to enable interfacing with devices at different supply voltages. Figure 10 shows a simplified diagram of the NRST pin ...

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... Figure 13. Touch Screen Operation ordinate measurement (Y) Revision V1.6/July 2010 ©2010 Semtech Corp. 15kV ESD Low Power 4-Wire / 5-Wire Resistive Touchscreen Controller with SPI Interface Y+ top conductive sheet bottom conductive sheet Figure 12. 4-wire Touch Screen Page 13 SX8652 DATASHEET ). T electrodes + Ypos ADC - www.semtech.com ...

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... ESD Low Power 4-Wire / 5-Wire Resistive Touchscreen Controller with SPI Interface Vref Vref - - ------------------- - Ypos Xpos = 4095 Vref - R4 Y- Page 14 SX8652 DATASHEET is created by the contact ------------------- - = 4095 ...

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... Figure 16). When some pressure is applied, a current path is created and brings X+ to the level defined by the resistive divider determined by R and the sum of R1 touchscreen, the bias delay is of 0.25 x POWDLY. Page 15 SX8652 DATASHEET -------------------------------- - z2 ...

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... Touchscreen Controller with SPI Interface top conductive sheet Figure 17. 5-wire touchscreen ------------------- - Ypos Xpos = 4095 Page 16 SX8652 DATASHEET electrodes Linearisation pattern ------------------- - = 4095 www.semtech.com ...

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... The host interface consists of SPI (DIN, DOUT, SCLK, NCS) and the NIRQ, NRST signals. The SPI implemented on the SX8652 is set to the common setting CPOL=0 and CPHA=0. It means data are sampled on the rising edge of the clock, and shifted on the falling one. The default state of the clock when NCS gets asserted is low ...

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... ADVANCED COMMUNICATIONS & SENSING Read/Write Registers Read Channels Data Host Commands 6.1.1. SPI Read/Write Registers The host can write to and read from registers of the SX8652 by the write and read commands as defined in Table 8. W/R command name 7 WRITE(RA) 0 READ(RA) 0 With the WRITE command, the host can write a single or multiple registers in the SX8652 register. This command is generated by setting the CMD(7:5) bits to write command (000) ...

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... Channel sequentially selected from RegChanMsk register, (see Table 13) Table 11. Channel definition Page 19 SX8652 DATASHEET Function 1 0 Bias channel (see Table 11 for CHAN) Bias channel (see Table 11 for CHAN) Wait POWDLY settling time Run conversion x x Enter manual or automatic mode. ...

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... SCLK DIN CMD DOUT 6.1.5. Invalid Qualified Data The SX8652 will return 0xFFFF data in case of invalid qualified data. This occurs: When the SX8652 has read all the channel data in the FIFO When a conversion is done without a pen being detected. Revision V1.6/July 2010 ©2010 Semtech Corp. ...

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... Revision V1.6/July 2010 ©2010 Semtech Corp. 15kV ESD Low Power 4-Wire / 5-Wire Resistive Touchscreen Controller with SPI Interface Register Description RegCtrl0 RegCtrl1 RegCtrl2 RegChanMsk RegStat RegSoftReset Table 12. Register address Page 21 SX8652 DATASHEET Write, Read Write, Read Write, Read Write, Read Read Write www.semtech.com ...

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... Digital filter control 00: Disable FILT 01: 3 sample averaging 10: 5 sample averaging 11: 7 sample acquisition, sort, average 3 middle samples Table 13. SX8652 Register Page 22 SX8652 DATASHEET Description 1000: 300 cps 1001: 400 cps 1010: 500 cps 1011: 1k cps ...

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... RegChanMsk The host status reading allows the host to read the status of the SX8652. The data goes from the SX8652 towards the host. Host writing to this register is ignored RegStat 4:0 00000 7:0 0x00 RegSoftReset Revision V1.6/July 2010 © ...

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... The POR of the SX8652 will reset all registers and states of the SX8652 at power-up. Additionally the host can reset the SX8652 by asserting the NRST pin (active low) and also via the SPI bus. If NRST is driven LOW, then NIRQ will be driven low by the SX8652. When NRST is released (or set to high) then NIRQ will be released by the SX8652. ...

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... ADVANCED COMMUNICATIONS & SENSING 7.1. Manual Mode In manual mode (RATE=0) single actions are triggered by the SPI commands described in Table 14. When a command is received, the SX8652 executes the associated task and waits for the next command the host to sequence all actions. Command ...

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... The PENTRIG mode offers the best compromise between power consumption and coordinate throughput. In this mode the SX8652 will wait until a pen is detected on the screen and then starts the coordinate conversions. The host will be signalled only when the screen is touched and coordinates are available. ...

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... If no registers are written, the circuit will start in manual mode. 8.2. Channel Selection The SX8652 can be setup to start a single channel conversion or to convert several channels in sequence. For a single conversion, the channel to be converted is determined from the CHAN(2:0) field in the command word (defined in Table 11) ...

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... An alternate conversion trigger method can be used with 4-wire touchscreen if the host system provides additional digital signals that indicate noisy or noise-free periods. The SX8652 can be set up to start conversions triggered by the AUX pin. A rising edge, a falling edge or both can trigger the conversion. To enter this mode, AUXACQ must be set to a different value than '00' as defined in Table 13 ...

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... ESD Low Power 4-Wire / 5-Wire Resistive Touchscreen Controller with SPI Interface + N POWDLY + SETDLY N chan PowDly SetDly Tconv [uS] [uS] [uS] 0 0.5 190 140 0.5 740 Table 15. Coordinate throughput examples Page 29 SX8652 DATASHEET – 21N + 1 filt osc filt Tcomm CoordRate [uS] [kSPS] 8 16.7 8 5.0 14 1.3 www.semtech.com ...

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... COMPANY'S MANUFACTURING GUIDELINES ARE MET. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD SHALL BE CONNECTED TO A SYSTEM GROUND PLANE. FAILURE MAY COMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE. Figure 27. DFN Package Land Pattern Page 30 SX8652 DATASHEET DIMENSIONS MILLIMETERS DIM MIN NOM ...

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... Figure 28. WLCSP Package Outline Drawing 1.00 0.50 0.25 NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS 2. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. Figure 29. WLCSP Land Pattern of WLCSP Page 31 SX8652 DATASHEET 0.50 1.50 12X Ø0.325 www.semtech.com ...

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... Semtech Ltd., Units 2 & 3, Park Court, Premier Way, Abbey Park Industrial Estate, Romsey, Hampshire, SO51 9DN. Tel: +44 (0)1794 527 600 Fax: +44 (0)1794 527 601 Revision V1.6/July 2010 ©2010 Semtech Corp Page 32 SX8652 DATASHEET ISO9001 CERTIFIED www.semtech.com ...