QT60168C-ASG-SL683 Atmel, QT60168C-ASG-SL683 Datasheet
QT60168C-ASG-SL683
Specifications of QT60168C-ASG-SL683
Related parts for QT60168C-ASG-SL683
QT60168C-ASG-SL683 Summary of contents
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Second generation charge-transfer QMatrix technology Keys individually adjustable for sensitivity, response time, and many other critical parameters Panel thicknesses to 50mm through any dielectric 16 and 24 touch key versions 100% autocal for life - no adjustments required SPI ...
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Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Overview . . . . . . . ...
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Overview QMatrix devices are digital burst mode charge-transfer (QT) sensors designed specifically for matrix geometry touch controls; they include all signal processing functions necessary to provide stable sensing under a wide variety of changing conditions. Only a few external ...
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For example: NKE = Number of keys enabled = 20 FDIL = Fast detect integrator limit = Burst spacing = 0.5ms FMEA = FMEA test time = 5ms NDIL = Norm detect integrator Limit = 2 HPR ...
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Figure 2-4 X-Drive Pulse Roll-off and Dwell Time Lost charge due to X drive inadequate settling before end of dwell time Dwell time Y gate Figure 2-5 Probing X-Drive Waveforms With a Coin Increasing the burst length (BL) parameter will ...
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Y within a solid perimeter (preferably) interdigitated as shown in Figure 2-6. For better surface moisture suppression, the outer perimeter of X should be as wide as possible, ...
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The pin is active low, and a low pulse lasting at least 10µs must be applied to this pin to cause a reset. To provide for proper operation during power transitions the ...
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Wiring Table 2.2 - Pin Listing Pin Function Vss 4 Vdd 5 Vss 6 Vdd Vref 11 S_Sync 12 SMP 13 DRDY 14 /SS 15 MOSI 16 ...
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Figure 2.7 Wiring Diagram See Table 2.2 for further connection information QT60248-AS R4.02/0405 ...
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Serial Communications These devices use SPI communications, in slave mode. The host device always initiates communications sequences; the QT is incapable of chattering data back to the host. This is intentional for FMEA purposes so that the host always ...
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MISO floats when /SS is high to allow multi-drop communications along with other slave parts. SCK - SPI clock - input only clock from host. The host must shift out data on the falling SCK ...
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Enter Setups Mode - 0x01 This command is used to initiate the Setups block transfer from Host to QT. The command must be repeated 2x within 100ms or the command will fail; the repeating command must be sequential without ...
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Report 1st Key - 0x06 Reports the first or only key to be touched, plus indicates if there are yet other keys that are also touched. The return bits are as follows: BIT Description 7 1= more than 1 ...
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Data Set for One Key - 0x4k Returns the data set for key k, where k = {0..23} encoded into the low nibble of this command. This command returns 5 bytes, in the sequence: Signal (2 bytes) Reference (2 ...
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Power On or Hardware Reset 0x0F Get 'Last command' 0xF0 not returned ~10ms Delay Keys OK Internal Host Processes Comms with QT Note: CRC errors or incorrect responses should cause each transmission to retry lQ Figure 4-1 Suggested Communications Flow ...
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Table 4.2 Command Summary Hex Name Description 0x00 Null command Used to get data back in SPI mode Enter Setups, stop sensing; followed by block load of binary Setups of length ‘nn’. Command must be repeated 2x consecutively without any ...
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Hex Name Description Returns Setups block area followed by CRC. 0x0D Dump Setups Scanning is halted and then auto-restarted after the cmd has completed. 0x0E Eeprom CRC Get eeprom CRC Return last 0x0F Returns last command received cmmd Get signal, ...
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Setups The devices calibrate and process all signals using a number of algorithms specifically designed to provide for high survivability in the face of adverse environmental challenges. They provide a large number of processing options which can be user-selected ...
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However, an obstruction over the sense pad, for which the sensor has already made full allowance for, could suddenly be removed leaving the sensor with an artificially suppressed reference level and thus become insensitive to touch. In this latter case, ...
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After the PRD interval has expired and the auto- recalibration has taken place, the affected key will once again function normally. PRD is fixed at 1 second for all keys, and cannot be altered. 5.7 Burst Length - BL The ...
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Shorter spacings result in a faster response time to touch; longer spacings permit higher burst lengths and longer conversion times but slow down response time. BS Default value: 1 (500µs) BS Possible range: 1..11 (500µs .. 3ms) 5.12 Lower Signal ...
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Table 5.1 Setups Block Setups data is sent from the host to the block of hex data. The block can only be loaded in Setups mode following two se quential 0x01 commands (page 12). All devices this ...
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Table 5.3 Setups Block Summary Typical values: For most touch applicatio ns, use the values shown in the outlined cells. Bold text items indicate default settings. The number to send to the QT is the number in the leftmost column ...
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Specifications 6.1 Absolute Maximum Electrical Specifications Operating temp ...
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Mechanical Dimensions SYMBOL 6.6 Marking +105 +105 ...
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Appendix 7.1 8-Bit CRC Algorithm // 8 bits crc calculation. Initial value polynomial = data bit number; unsigned char eight_bit_crc(unsigned char crc, unsigned char data) { unsigned char ...
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Key Layout This key design can be made on a 1-sided SMT PCB. A single 0-ohm jumper allows the wiring to be done on a single side with full pass-through of X and Y traces to allow matrix ...
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Tel: +44 (0)23 8056 5600 Fax: +44 (0)23 8045 3939 This device covered under one or more of the following United States and international patents: 5,730,165, 6,288,707, 6,377,009, 6,452,514, 6,457,355, 6,466,036, 6,535,200. Numerous further patents are pending which may ...