sx8654evk Semtech Corporation, sx8654evk Datasheet
sx8654evk
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sx8654evk Summary of contents
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... I RDERING NFORMATION Part Number Package SX8657IWLTRT QFN-20 SX8657ICSTRT WLCSP-19 SX8658IWLTRT QFN-20 SX8658ICSTRT WLCSP-19 SX8654EVK Evaluation Kit th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing RODUCT Low Voltage Operation 2.3V to 3.6V Supply Integrated Low Drop Out (LDO) Regulator Low Power Consumption 30uA@2 ...
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ADVANCED COMMUNICATIONS & SENSING G D ..................................................................................................................... 1 ENERAL ESCRIPTION T A ..................................................................................................................... 1 YPICAL PPLICATIONS O I ................................................................................................................... 1 RDERING NFORMATION .................................................................................................................. 1 EY RODUCT EATURES 1 G ENERAL DESCRIPTION 1.1 Marking Information 1.1.1 SX8657 1.1.2 ...
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ADVANCED COMMUNICATIONS & SENSING 5.3.6 PROXSTAT Update 5.4 Host Operation 5.4.1 General Description 5.4.2 Proximity Sensing vs Touch Operations 5.4.3 Minimum Scan Period (i.e. PROXSCANPERIOD (SX8657/58) .......................................................................................... 35 APTICS NTERFACE 6.1 Introduction 6.2 ERM Load 6.2.1 Introduction ...
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ADVANCED COMMUNICATIONS & SENSING 1 G ENERAL DESCRIPTION 1.1 Marking Information 1.1.1 SX8657 Figure 1 – Marking Information – QFN(left) – CSP(right) 1.1.2 SX8658 Figure 2 – Marking Information – QFN(left) – CSP(right) th Rev 1 – 25 July 2011 ...
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ADVANCED COMMUNICATIONS & SENSING 1.2 Pin Diagrams 1.2.1 QFN Package 1.2.2 CSP Package th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Figure 3 – Pin Diagram – QFN Figure 4 – Pin Diagram - CSP ...
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ADVANCED COMMUNICATIONS & SENSING 1.3 Pin Description Name Type Description VDD P Main Power Supply GND P Main Ground VREG P Internal Regulator Output (must be connected to an external capacitor; see § 13) MVDD P Haptics Motor Power Supply ...
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ADVANCED COMMUNICATIONS & SENSING th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Figure 6 – SX8658 Block Diagram 7 SX8657/SX8658 Haptics Enabled 4/5-Wire www.semtech.com ...
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ADVANCED COMMUNICATIONS & SENSING LECTRICAL HARACTERISTICS 2.1 Absolute Maximum Ratings Stress above the limits listed in the following table may cause permanent failure. Exposure to absolute ratings for extended time periods may affect device reliability. The limiting ...
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ADVANCED COMMUNICATIONS & SENSING Symbol Description MVDD Haptics supply voltage MIDD Haptics supply current Digital I/Os (ADDR, SCL, SDA, NRST, NIRQ, AUX1, AUX2, AUX3, MIN) VIH High level input voltage VIL Low level input voltage ILEAK Input leakage current CI ...
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ADVANCED COMMUNICATIONS & SENSING Symbol Description Reset VPOR Power-On-Reset voltage t Reset time after POR RESET t Reset pulse from host uC PULSE I2C Interface f SCL clock frequency SCL Hold time (repeated) START t HD;STA condition t LOW period ...
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ADVANCED COMMUNICATIONS & SENSING YPICAL PERATING HARACTERISTICS Conditions as defined in § 2. +25° C, VDD=VDDM=3.3V unless otherwise specified. A IDD_OFF vs VDD vs TEMP 4.00E-07 3.80E-07 3.60E-07 3.40E-07 3.20E-07 3.00E-07 2.80E-07 2.60E-07 2.40E-07 ...
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ADVANCED COMMUNICATIONS & SENSING OUCHSCREEN NTERFACE 4.1 Introduction The purpose of the touchscreen interface is to measure and extract touch information like coordinates and pressure. This is done in two steps, first an ADC measures the analog ...
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ADVANCED COMMUNICATIONS & SENSING Higher reliability and better endurance are the advantages of 5-wire touchscreens but they do not allow pressure measurement 4.2 Coordinates Measurement 4.2.1 4-wire Touchscreen The electrode plates are internally connected through terminals X+, X- and Y+, ...
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ADVANCED COMMUNICATIONS & SENSING 4.2.2 5-wire Touchscreen 5-wire touchscreen coordinates measurement is performed similarly by biasing opposite corner pairs in either directions on the lower panel, and converting the voltage appearing on the wiper panel with the ...
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ADVANCED COMMUNICATIONS & SENSING Re-arranging z1 and z2 gives: This finally results in: The touch resistance calculation above hence requires three channel measurements (Ypos, z2 and z1) and one specification data (Rytot). An alternative calculation method is using Xpos, Ypos, ...
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ADVANCED COMMUNICATIONS & SENSING Figure 13 – 4-wire Touchscreen Pen Detection When using a 5-wire touchscreen, the pen detection pull-up resistor R monitor the X+/BR pin as in 4-wire mode. The top panel is grounded via the WIPER pin to ...
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ADVANCED COMMUNICATIONS & SENSING Figure 15 – Digital Processing Block Diagram FILT Nfilt Function average ADC samples are averaged ADC samples are ...
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ADVANCED COMMUNICATIONS & SENSING 4.6 Host Operation 4.6.1 Overview The chip has three operating modes that are configured using the I2C as defined in § Manual (command ‘MAN’ and TOUCHRATE = 0). Pen detect (command ‘PENDET’ and TOUCHRATE ...
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ADVANCED COMMUNICATIONS & SENSING In case the range of POWDLY settings available is not enough to cover the required settling time, one can use the SELECT command first to bias the channel, and then send the CONVERT command hence extending ...
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ADVANCED COMMUNICATIONS & SENSING Pen Touch TOUCHRATE tick PENSTAT CONVSTAT NIRQ I2C Read Channel Idle Touch Conversion Pen Detection Figure 21 – Pen Trigger Mode (RegIrqMsk[3: PROXSCANPERIOD = 0) Please note that to prevent data loss, the ...
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ADVANCED COMMUNICATIONS & SENSING TOUCHRATE tick NIRQ I2C Read Channel Idle Pen Detection Figure 23 – Incorrect (too high) TOUCHRATE setting In order to prevent this, one can estimate the maximum throughput achievable and set TOUCHRATE parameter accordingly. Tcom is ...
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ADVANCED COMMUNICATIONS & SENSING ROXIMITY ENSING NTERFACE 5.1 Introduction The purpose of the proximity sensing interface is to detect when a conductive object (usually a body part i.e. finger, palm, face, etc the proximity ...
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ADVANCED COMMUNICATIONS & SENSING 5.2 Analog Front-End (AFE) 5.2.1 Capacitive Sensing Basics Capacitive sensing is the art of measuring a small variation of capacitance in a noisy environment. mentioned above, the chip’s proximity sensing interface is based on capacitive sensing ...
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ADVANCED COMMUNICATIONS & SENSING The challenge of capacitive sensing is to detect this relatively small variation of C for a few percents only) and differentiate it from environmental noise (C environment characteristics like temperature, etc). For this purpose, the chip ...
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ADVANCED COMMUNICATIONS & SENSING 5.2.3 Capacitance-to-Voltage Conversion (C-to-V) PROXSENSORCON defines which pin will act as the sensor during proximity sensing operations. In the typical case, the touchscreen top layer is used as the sensor (exact pin/electrode depends on screen type/structure). ...
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ADVANCED COMMUNICATIONS & SENSING Block startup: a compensation is automatically requested when the proximity sensing is enabled via PROXSCANPERIOD. I2C: a compensation can be manually requested anytime by the host through I2C interface. PROXAVG update: a compensation can be automatically ...
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ADVANCED COMMUNICATIONS & SENSING Digital processing block also updates CONVSTAT (set during proximity operations) and PROXCOMPSTAT (set when compensation is currently pending execution or competition) 5.3.2 PROXRAW Update PROXRAW update consists mainly in starting the AFE and waiting for the ...
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ADVANCED COMMUNICATIONS & SENSING 5.3.3 PROXUSEFUL Update PROXUSEFUL update consists in filtering PROXRAW upfront to remove its potential high frequencies components(system noise, interferer, etc) and extract only user activity (few Hz max) and slow environment changes. F(PROXRAW ; PROXUSEFUL[n-1] ; ...
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ADVANCED COMMUNICATIONS & SENSING 5.3.4 PROXAVG Update PROXAVG update consists in averaging PROXUSEFUL to ignore its “fast” variations (i.e. user finger/palm/hand) and extract only the very slow variations of environment capacitance C One can program positive and negative debounced thresholds ...
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ADVANCED COMMUNICATIONS & SENSING F(PROXUSEFUL ; PROXAVG[n-1] ; PROXAVGxxxFILT PROXAVGxxxFILT).PROXUSEFUL + PROXAVGxxxFILT.PROXAVG[n-1] xxx = POS or NEG th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Figure 36 – ProxAvg Update 30 SX8657/SX8658 ...
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ADVANCED COMMUNICATIONS & SENSING 5.3.5 PROXDIFF Update PROXDIFF update consists in the complementary operation i.e. subtracting PROXAVG to PROXUSEFUL to ignore slow capacitances variations (C 5.3.6 PROXSTAT Update PROXSTAT update consists in taking PROXDIFF information (C threshold PROXTHRESH and finally ...
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ADVANCED COMMUNICATIONS & SENSING 5.4 Host Operation 5.4.1 General Description If PROXIRQSEL = 0, an interrupt can be triggered when the user is detected to be close, detected to be far, or both (PROXCLOSEIRQEN, PROXFARIRQEN). User in range PROXSCANPERIOD tick ...
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ADVANCED COMMUNICATIONS & SENSING touchscreen is used as the proximity sensor and is being touched when the conversion is performed, the proximity measurement result may be incorrect. CONVERT Y I2C Channel Bias Channel Conv e rsion CONVSTAT NIRQ (RegIrqMsk[6:3]=0001) Figure ...
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ADVANCED COMMUNICATIONS & SENSING Pen Touch TOUCHRATE tick PENSTAT CONVSTAT NIRQ I2C Read Channel Idle Touch Conversion Pen Detection Proximity Sensing Figure 44 – Pen Trigger Mode (RegIrqMsk[6:2] = 00010 ; PROXSCANPERIOD = 001 ie 1/TOUCHRATE) 5.4.3 Minimum Scan Period ...
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ADVANCED COMMUNICATIONS & SENSING (SX8657/58) APTICS NTERFACE 6.1 Introduction Haptics technology is commonly used in systems which include a touchscreen interface. Its purpose is to provide tactile feedback to the user to acknowledge a touch event hence ...
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ADVANCED COMMUNICATIONS & SENSING If AmplitudeCode is within HAPTSQUELCH range (for more than 512/MIN_Freq in PWM mode, for more than 512/FOSCL in I2C mode): Else: VMOUT(V) = (AmplitudeCode / 127) x 1.135 * HAPTGAIN AmplitudeCode (signed) is defined differently depending ...
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ADVANCED COMMUNICATIONS & SENSING The carrier frequency of VMOUT_Freq is defined as following: VMOUT_Freq(Hz) = (MIN_Freq / HAPTRANGE) VMOUT_Freq(Hz) = (MIN_Freq / HAPTRANGE) / (HAPTTIMER +1) If AmplitudeCode is within HAPTSQUELCH range (for more than 512/VMOUT_Freq): Else: VMOUT_Envelope(V) = (AmplitudeCode ...
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ADVANCED COMMUNICATIONS & SENSING EMPERATURE ENSOR The chip includes a temperature sensor which monitors the chip’s junction temperature. Its purpose is to provide over-temperature information to the host and if needed automatically shutdown chip operation for thermal ...
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ADVANCED COMMUNICATIONS & SENSING 8 I (NIRQ) NTERRUPT 8.1 Introduction The purpose of the NIRQ pin is to indicate to the host (via a falling edge) when any of the events considered being time-critical has occurred. Non time-critical events can ...
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ADVANCED COMMUNICATIONS & SENSING (AUX1/AUX2/AUX3) UXILIARY INS The chip has three auxiliary pins which can be used the touchscreen interface when using a 5-wire touchscreen (WIPER=AUX1 the proximity sensing interface (PROXSENSORCON and PROXSHIELDCON) ...
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ADVANCED COMMUNICATIONS & SENSING 10 R ESET 10.1 Hardware (POR and NRST) The chip generates its own power on reset (POR) signal after a power supply is connected to the VDD pin. NRST input pin can be used to reset ...
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ADVANCED COMMUNICATIONS & SENSING 11 I2C I NTERFACE 11.1 Introduction The chip is a read-write slave-mode I2C device and complies with the Philips I2C standard Version 2.1 dated January, 2000. The chip has a few user-accessible internal 8-bits registers to ...
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ADVANCED COMMUNICATIONS & SENSING The correct sampling of the screen by the chip and the host I2C bus traffic are events that might occur simultaneously. The chip will synchronize these events by the use of clock stretching if that is ...
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ADVANCED COMMUNICATIONS & SENSING Command Command(7:0) SELECT CONVERT MAN PENDET PENTRG Channel Chan(2: ...
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ADVANCED COMMUNICATIONS & SENSING The 3 bits CHAN(2:0) are defined in the previous table and show which channel data is referenced. The channel data D(11: unsigned format and corresponds to a value between 0 and 4095. The chip ...
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ADVANCED COMMUNICATIONS & SENSING EGISTERS ETAILED ESCRIPTION Address Name Default 0x00 RegTouch0 0x00 0x01 RegTouch1 0x20 0x02 RegTouch2 0x00 0x03 RegTouch3 0x00 0x04 RegChanMsk 0xC0 0x05 RegHapt0 0x00 0x06 RegHapt1 0x00 0x07 RegHapt2 0x00 0x08 RegHapt3 ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable Default 7:4 TOUCHRATE 0000 3:0 POWDLY 0000 Bits Variable Default 7:5 Reserved 001 4 TSTYPE 0 3:2 RPNDT 00 th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Description Defines ...
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ADVANCED COMMUNICATIONS & SENSING 1:0 FILT 00 Bits Variable Default 7:4 Reserved 0000 3:0 SETDLY 0000 Bits Variable Default 7:0 Reserved 0x00 Bits Variable Default 7 XCONV 1 6 YCONV 1 5 Z1CONV 0 4 Z2CONV 0 3:0 Reserved 0000 ...
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ADVANCED COMMUNICATIONS & SENSING 6:5 HAPTTYPEEN 00 4 HAPTRANGE 0 3:0 HAPTGAIN 0000 Bits Variable Default 7:6 Reserved 00 5:3 HAPTSQUELCH 000 2 TEMPWRNIRQEDG 0 1 TEMPALRMIRQEDG 0 0 TEMPALWAYSON 0 th Rev 1 – 25 July 2011 Resistive Touchscreen ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable Default 7:0 HAPTAMP 0x00 Bits Variable Default 7:5 HAPTBW 100 4 HAPTHZ 0 3 HAPTSHORTPROT 0 2:0 HAPTTIMERMSB 000 Bits Variable Default 7:0 HAPTTIMERLSB 0x00 Bits Variable Default 7:0 Reserved 0x00 Bits Variable Default ...
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ADVANCED COMMUNICATIONS & SENSING 5:4 PROXHYST 00 3:0 PROXSCANPERIOD 0000 Bits Variable Default 7:0 PROXTHRESH 0x00 Bits Variable Default 7:6 PROXCLOSEDEB 00 5:4 PROXFARDEB 00 3:0 PROXCOMPPRD 0000 Bits Variable Default 7:0 PROXSTUCK 0x00 Bits Variable 7:0 PROXAVGPOSTHRESH th Rev ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable Default 7:5 PROXAVGPOSDEB 000 4:2 PROXAVGPOSFILT 000 1:0 PROXRAWFILT 00 Bits Variable 7:0 PROXAVGNEGTHRESH Bits Variable Default 7:5 PROXAVGNEGDEB 000 4:2 PROXAVGNEGFILT 000 1 PROXHIGHIM 0 0 Reserved 0 th Rev 1 – 25 ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable Default 7:4 Reserved 0000 3:0 PROXRAWMSB 0000 Bits Variable Default 7:0 PROXRAWLSB 0x00 Bits Variable Default 7:4 Reserved 0000 3:0 PROXUSEFULMSB 0000 Bits Variable Default 7:0 PROXUSEFULLSB 0x00 Bits Variable Default 7:4 Reserved 0000 ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable Default 7:0 PROXOFFSETLSB 0x00 Bits Variable Default 7 Reserved 0 6:4 PROXSENSITIVITY 000 3:1 PROXFREQ 000 0 Reserved 0 Bits Variable Default 7:4 PROXSENSORCON 0000 3:0 PROXSHIELDCON 0000 Bits Variable Default 7:6 Reserved 00 ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable 7 HAPTSHORTIRQEN 6 PROXCLOSEIRQEN 5 PROXFARIRQEN/ PROXCONVDONEIRQEN 4 PROXCOMPDONEIRQEN 3 PENTOUCHIRQEN/ TOUCHCONVDONEIRQEN 2 PENRELEASEIRQEN 1 TEMPWARNINGIRQEN 0 TEMPALARMIRQEN Bits Variable 7 HAPTSHORTIRQ 6 PROXCLOSEIRQ 5 PROXFARIRQ/ PROXCONVDONEIRQ 4 PROXCOMPDONEIRQ 3 PENTOUCHIRQ/ TOUCHCONVDONEIRQ 2 PENRELEASEIRQ ...
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ADVANCED COMMUNICATIONS & SENSING 5 PROXSTAT 4 PROXCOMPSTAT 3 CONVSTAT 2 PENSTAT 1 TEMPWARNINGSTAT 0 TEMPALARMSTAT Bits Variable 7 Reserved 6 AUX1DIGOUTEN 5 AUX2DIGOUTEN 4 AUX3DIGOUTEN 3:0 AUX1DIGOUT th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity ...
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ADVANCED COMMUNICATIONS & SENSING Bits Variable 7:4 AUX2DIGOUT 3:0 AUX3DIGOUT Bits Variable 7:0 SOFTRESET th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Default Description 0000 Defines the digital signal to output on AUX2 : 0000 ...
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ADVANCED COMMUNICATIONS & SENSING PPLICATION NFORMATION 13.1 Typical Application Circuit 13.2 External Components Recommended Values Symbol Description CVDD Main supply decoupling capacitor CMVDD Motor supply decoupling capacitor CVREG Regulator decoupling capacitor RPULL Host interface pull-ups Proximity sensor-to-shield ...
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ADVANCED COMMUNICATIONS & SENSING ACKAGING NFORMATION 14.1 QFN Package th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Figure 56 - Outline Drawing - QFN Figure 57 - Land Pattern - QFN 59 ...
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ADVANCED COMMUNICATIONS & SENSING 14.2 CSP Package th Rev 1 – 25 July 2011 Resistive Touchscreen Controller with Proximity Sensing Figure 58 - Outline Drawing - CSP Figure 59 - Land Pattern - CSP 60 SX8657/SX8658 Haptics Enabled 4/5-Wire www.semtech.com ...
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... Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. Contact Information Semtech Corporation Advanced Communications and Sensing Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 th Rev 1 – ...