QT60248-ASG Atmel, QT60248-ASG Datasheet
QT60248-ASG
Specifications of QT60248-ASG
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QT60248-ASG Summary of contents
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... These devices makes use of an important new variant of charge-transfer sensing, transverse charge-transfer matrix format that minimizes the number of required scan lines. Unlike older methods, it does not require one IC per key. -40 -40 LQ QProx™ QT60168, QT60248 Appliance controls Outdoor keypads AVAILABLE OPTIONS T # Keys +105 QT60168-ASG +105 QT60248-ASG 16 QT60248 VSS 3 QT60168 VDD 4 VSS 5 TQFP-32 VDD ...
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... QT60248-AS R4.02/0405 ...
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... QmBtn software for the PC can be used to program the operation of the IC as well as read back key status and signal levels in real time. The QT60168 and QT60248 are electrically identical with the exception of the number of keys which may be sensed. 1.1 Part differences Versions of the device are capable of a maximum keys (QT60168, QT60248 respectively) ...
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... Figure 2-1 VCs - Non-Linear During Burst (Burst too long too small, or X-Y capacitance too large) Figure 2-2 VCs - Poor Gain, Non-Linear During Burst (Excess capacitance from Y line to Gnd) Figure 2-3 Vcs - Correct 4 QT60248-AS R4.02/0405 ...
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... The overall key size can range from 10mm x 10mm up to 100mm x 100mm but these are not hard limits. The keys can be any shape including round, rectangular, square, etc. The internal pattern 5 QT60248-AS R4.02/0405 ...
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... Errors can be observed after a cal cycle using the 0x8k command (see Section 4.16). 2.13 Reset Input The /RST pin can be used to reset the device to simulate a power down cycle, in order to bring the part up into a known 6 QT60248-AS R4.02/0405 Cal Time, ms, 24 keys 228 309 390 ...
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... Failing that, a small ceramic capacitor, for example 3pF, can be added between the X and Y lines serving the key to artificially boost signal strength. For those applications requiring it, Quantum can supply sample FMEA test data on special request. 7 QT60248-AS R4.02/0405 ...
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... X1 matrix drive line O X2 matrix drive line 8 If Unused, Connect To.. Leave open Leave open - - - - Leave open Leave open Leave open - Leave open - - - - - - - Vdd - - Leave open Leave open Leave open Leave open Leave open or Vdd Leave open Leave open Leave open QT60248-AS R4.02/0405 ...
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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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... Recommended Values of Ra & Ca SPI Clock Rate Ra 1.5MHz 680 400kHz 1,000 100kHz 2,200 50kHz 2,200 10 High Falling Rising 1.5MHz QT60xx8 DRDY SS SCK MISO MOSI QT60xx8 Circuit X drives DRDY ( shown) SS SCK MISO Y Lines MOSI 1K shown) RESET Ca 100pF 270pF 470pF 1nF QT60248-AS R4.02/0405 ...
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... New commands during intermediate byte shift-out operations are ignored, and null bytes should always be used. Figure 3-3 SPI Slave-Only Mode Timing S2: [20ns S3: m25ns S6: m1µs S7: m333ns {optional 2nd command byte} S4 3-state S4: [20ns S8: m333ns S9: m667ns {null byte or next command to get QT response data response QT60248-AS R4.02/0405 ...
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... Bit 1: Set if any key is in the process of calibrating. Bit 0: Set if any key is in detection (touched). A CRC byte is appended to the response to the 0x05 command; this CRC folds in the command value 0x05 itself initially. 12 QT60248-AS R4.02/0405 ...
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... This command returns a 1-byte internal code. A CRC byte is appended to the response; this CRC folds in the command 0x10 itself initially. 4.14 Internal Code - 0x12 This command returns an internal code byte of the part for factory diagnostic purposes. A response might take as long as 500ms. No CRC is appended to the response QT60248-AS R4.02/0405 ...
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... An eeprom CRC error report is serious, and requires that the host reload the Setups table into the device and thereafter issue a reset command or hardware reset. The ‘Last Command’ command can be used at any time to clear comms error flags and to resynchronize failed communications, for example due to timing errors etc. 14 QT60248-AS R4.02/0405 ...
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... Get General Status Error Flag (takes Comms 'Last command' Error (clear error) calibration fail, or FMEA fail, or multiple errors Error Handling FMEA Calibration Error Error 0x0B 0x0C Get Get Errors for All FMEA Status Keys QT60248-AS R4.02/0405 0x04 0x0F Get resolvable error ...
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... CRC-8 of cmmd + return data 0..0xFF 1 4 Yes 4th return byte is CRC-8 of cmmd + return data 3 bytes 0..0xFF Yes 1 4 4th return byte is CRC-8 of cmmd + return data 3 bytes 1 2 0..0xFF Yes 2nd return byte is CRC-8 of cmmd + return data 16 Notes Page QT60248-AS R4.02/0405 ...
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... Second return byte is CRC of cmmd + return data Used in Run mode. Normal sensing of other keys not affected. CAL of ‘k’ only takes place in the key’s normal timeslot ~0xCk Returns the ones compliment of the cmd char, once the cal is scheduled. 17 Notes Page QT60248-AS R4.02/0405 ...
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... Decreasing signals should not be compensated quickly, since an approaching finger could be compensated for partially or entirely before even touching the touch pad. Figure 5-1 Thresholds and Drift Compensation Reference Hysteresis Threshold Signal Output 18 QT60248-AS R4.02/0405 ...
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... It is almost always desirable in these cases to cause the key to recalibrate quickly restore normal touch operation. The time required to do this is governed by PRD. In order for this to work, the signal must rise through the positive threshold level PTHR continuously for the PRD period. 19 QT60248-AS R4.02/0405 ( seconds) 20 (10 seconds) ...
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... This is an alterable parameter which affects all keys. The burst spacing can be viewed as a scheduled timeslot in which a burst occurs. This approach results in an orderly and predictable sequencing of key scanning with predictable response times. 0 (Off (Off) 0 (Off ) 0, 1 (Off, On) QT60248-AS R4.02/0405 ...
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... This parameter occupies 2 bytes of the setups table. The low order byte should be sent first. LSL Default value: 100 LSL Possible range: 0..2047 5.13 Host CRC - HCRC The setups block terminates with a 8-bit CRC, HCRC, of the entire block. The formulae for calculating this CRC is shown in Section 7. 21 QT60248-AS R4.02/0405 ...
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... Bit 6 = Mains sync, negative edge enabled; default = 0 (off 0.. Lower nibble = burst spacing Lower limit of acceptable signal; below this value, device declares an error. 0..2048 16 24 100 The low order byte should be sent first. 0..255 Bit (X line Note: Byte 0 is returned first QT60248-AS R4.02/0405 Page ...
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... Default= 10s AKS Scope Sync MSYNC Per key Per key Global 16 - Off - - Off - QT60248-AS R4.02/0405 BS Global - Off - unused On - 500µs - 750µs 1,000µs 1,250µs 1,500µs 1,750µs 2,000µs 2,250µs 2,500µs 2,750µs 3,000µs ...
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... SPI parameter controlled by host ns SPI parameter controlled SPI parameter controlled by host ns SPI parameter controlled by QT µs SPI parameter controlled by QT µs SPI parameter controlled SPI parameter controlled by host ns SPI parameter controlled by host ns SPI parameter controlled by host MHz Max guaranteed is a min of 1.5MHz QT60248-AS R4.02/0405 ...
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... Min Max Notes 6.90 7.10 SQ 8.75 9.25 SQ 0.09 0.20 0.45 0.75 0.05 0.15 - 1.20 0.30 0.45 0.80 0.80 BSC 0 7 TQFP Part Number Keys QT60168-ASG 16 QT60248-ASG Inches Min Max 0.272 0.280 0.344 0.354 0.003 0.008 0.018 0.030 0.002 0.006 - 0.047 0.012 ...
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... If(fb) { crc ^= 0x8c while(--index); return crc CRC calculator for Windows is available free of charge from Quantum Research crc bit number // shift counter // initialise the shift counter 26 QT60248-AS R4.02/0405 ...
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... PCB Layout Shown is an example PCB layout using inexpensive 1-sided CEM-1 or FR-1 PCB laminate. The key layouts follow the design rules shown above. (PCB design shown uses a QT60326 chip but still represents a good example QT60248-AS R4.02/0405 Y 0-ohm SMT Jumper X Y ...
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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 ...