QT60168-ASG QUANTUM ATMEL, QT60168-ASG Datasheet
QT60168-ASG
Specifications of QT60168-ASG
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QT60168-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 ...
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Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Overview . . . . . . . ...
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... QT60168. On the QT60168, only the first 2 Y lines (Y0, Y1) are operational by default. On the QT60168, to use keys located on line Y2, one or more of the pre-enabled keys must be disabled simultaneously while enabling the desired new keys ...
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... QmBtn software is available free of charge on Quantum’s website. The signal swing from the smallest finger touch should preferably exceed 10 counts, with 15 being a reasonable target. The signal threshold setting (NTHR) should be set to a value guaranteed to be less than the signal swing caused by the smallest touch ...
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... Figure 2-6 Recommended Key Structure ‘T’ should ideally be similar to the complete thickness the fields need to penetrate to the touch surface. Smaller dimensions will also work but will give less signal strength doubt, make the pattern coarser. The upper limits of Rx and Ry are reached when the signal level and hence key sensitivity are clearly reduced ...
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... See Section 2.16 for guidance about potential FMEA problems with small key shapes. 2.10 PCB Layout, Construction It is best to place the chip near the touch keys on the same PCB reduce X and Y trace lengths, thereby reducing the chances for EMC problems. Long conn ection traces act as RF antennae ...
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... Example: If the limit value is 10, then the device has to detect a threshold crossing 10 times in succession without interruption, before the key is declared to be touched any sample the signal is not seen to cross the threshold level, the counter is cleared and the process has to start over from the beginning. ...
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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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... 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. ...
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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 key is active 6 1= any error condition is present 5 Unused ...
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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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... Bit 6: 1= any of the following conditions prevail: calibrating, key(s) failed cal 5 times, sync fail, comms error, FMEA failure 0..0xFF Yes Bit 5: Unused Bits 4..0: indicates key number (0..23) of first key touched; reads 0x1F (31 decimal touch. 2nd return byte is CRC-8 of cmmd + return data 0..0xFF 1 4 Yes ...
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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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... When a finger is sensed, the signal falls since the human body acts to absorb charge from the cross-coupling between X and Y lines. An isolated, untouched foreign object (a coin water film) will cause the signal to rise very slightly due to an enhancement of coupling. This is contrary to the way most capacitive sensors operate ...
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... DI counter mechanism that acts to confirm a detection by consensus (all detections in sequence must agree). The DI mechanism counts sequential detections of a key that appears to be touched, after each burst for the key. For a key to be declared touched, the DI mechanism must count to completion without even one detection failure. ...
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... AKS permits the suppression of multiple key presses based on relative signal strength. This feature assists in solving the problem of surface moisture which can bridge a key touch to an adjacent key, causing multiple key presses. This feature is also useful for panels with tightly spaced keys, where a fingertip might inadvertently activate an adjacent key ...
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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 Limit - LSL This Setup determines the lowest acceptable value of signal level for all keys. If any key’ ...
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... Some commands return bitfields related to keys. For example, command 0x07 (report all keys) returns 3 bytes containing flag bits, one per key, to indicate which keys are reporting touches. The following table shows the byte and bit order of the keys. The table contains the key number reported in each bit. ...
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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 (0..15), not numbers from within the table. The QT uses lookup tables to translate the 0..15 to the parameters for each function. ...
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Specifications 6.1 Absolute Maximum Electrical Specifications Operating temp ...
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... Package Type: 32 Pin TQFP Millimeters 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 ...
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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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... Terms and Conditions of sale and supply of services which are available online at www.qprox.com and are supplied with every order acknowledgement. QProx, QTouch, QMatrix, QLevel, QSlide, and QWheel are trademarks of QRG. QRG products are not suitable for medical (including lifesaving equipment), safety or mission critical applications or other similar purposes. Except as expressly set out in QRG's Terms and Conditions, no licenses to patents or other intellectual property of QRG (express or implied) are granted by QRG in connection with the sale of QRG products or provision of QRG services ...