qt60325 Quantum Research Group, qt60325 Datasheet
qt60325
Related parts for qt60325
qt60325 Summary of contents
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... Security keypanels Industrial keyboards The QT60325, QT60485, and QT60645 digital charge-transfer (“QT”) QMatrix™ ICs are designed to detect human touch 32, 48 keys respectively using a scanned, passive X-Y matrix. It will project the keys through almost any dielectric, e.g. glass, plastic, stone, ceramic, and even wood thicknesses more. The touch areas are defined as simple 2-part interdigitated electrodes of conductive material, like copper or screened silver or carbon deposited on the rear of a control panel. Key sizes, shapes and placement are almost entirely arbitrary ...
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... Quantum Research Group Ltd. Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 Field Flows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Circuit Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.3 Matrix Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.4 Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Signal Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1 Negative Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Positive Threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 Hysteresis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4 Drift Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 Detection Recalibration Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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... X7 Drive matrix scan gate control to drive Y dwell timing circuit Slave select for SPI direction control; active low I/ Input O = Output Pwr = Power pin I/O = Bi-directional line PP = Push Pull output drive OD = Open drain output drive lQ ©Quantum Research Group Ltd. iii www.qprox.com QT60xx5 / R1.05 ...
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... Quantum Research Group Ltd. Figure 1-2 Sample Electrode Geometries PARALLEL LINES edge transitions of the X drive pulse. The charge emitted by the X electrode is partly received onto the corresponding Y electrode which is then processed ...
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... Integrator R eset Integrator R eset harge C ancellation 1 C harge C ancellation harge C ancellation 2 C harge C ancellation © Quantum Research Group Ltd. Sample Sample switch ( switch ( Cancellation Cancellatio n switches switches 1 1 Res et sw itch ...
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... Once a finger is sensed, the drift compensation mechanism ceases since the signal is legitimately detecting an object. Drift compensation only works lQ © Quantum Research Group Ltd. when the signal in question has not crossed the negative threshold level (Section 2.1). The drift compensation mechanism can be made asymmetric if desired ...
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... This interval can be set on a per-key basis; it can also be disabled by setting ^K to zero. lQ © Quantum Research Group Ltd. 2.8 Reference Guardbanding See also commands ^N, ^O, page 27; L, page 28 QT60xx5 devices provide for a method of self-checking that allows the host device to ascertain whether one or more key reference levels are 'out of spec' ...
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... The time required for recalibration is dependent on the burst spacing setting ^G (Section 3.8). lQ © Quantum Research Group Ltd. Individual keys or groups of keys can be recalibrated with a single command depending on the current command scope. The time required to recalibrate many keys is not multiplicative ...
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... QT60xx5 parts use identical circuits and operate in identical manner in all respects, except that only the QT60645 can acquire 64 keys. The QT60325 and QT60485 only acquire 32 and 48 keys respectively, but both still use an 8x8 matrix; any keys in the matrix can be used. Unused keys must be disabled by setting their burst length to zero (command ^F) ...
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... Quantum Research Group Ltd. 10 www.qprox.com QT60xx5 / R1.05 ...
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... Quantum Research Group Ltd. 11 www.qprox.com QT60xx5 / R1.05 ...
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... RFI; in fact, they act as ‘sinks’ for RFI emitted by the X lines since they are virtual grounds. Series-R in the Y lines is not required for RFI suppression, and in fact series-R can introduce cross-talk among keys. lQ © Quantum Research Group Ltd. 3.5 OISE External noise, sometimes caused by ground bounce due to ...
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... Figure 3-1). To eliminate leakage current issues the amplifier should be a JFET or CMOS input type only. TI’s lQ © Quantum Research Group Ltd. TLC2272 type opamp is a good example of the type of device which should be employed. Figure 3-1 Circuit: The first opamp is a charge integrator whose output ranges between ...
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... An external TTL-compatible lQ © Quantum Research Group Ltd. frequency source can also be connected to XTI; XTO should be left unconnected. The frequency of oscillation should be 6MHz +/-2%. 3.16 Startup / Calibration Times The QT60xx5 requires initialization times as follows: 1 ...
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... In the reference circuit show in Figure 3-1, the JFET will reset lQ © Quantum Research Group Ltd. Cs when the drive signal is low should be set to ‘0’. Figure 3-2 requires that ^S be set to ‘1’. ...
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... MOSI MOSI SS Vdd MS lQ © Quantum Research Group Ltd. Bypass capacitors and series resistors can be used to prevent these effects as shown in Figures 4-4 and 4-5. 4 Serial Interface QT60xx5 devices use an SPI serial interface to a host MCU. This port uses a protocol described in Section 5. 4.1 Serial Port specifications ...
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... Setup - Put (affect 64 keys) Lock Reference Levels ('L') command Calibrate command (all keys) Get key errors (E), Get keys pushed (K) All other commands lQ © Quantum Research Group Ltd. Figure 4-2 SPI Slave-Only Mode Timing T dr1 Optional Byte 2 Null Dummy Data ...
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... For 2-byte functions, (1) is repeated with a m50µs delay. lQ © Quantum Research Group Ltd. 3) When the sensor has the command echo or requested data ready to send back to the host, it loads it into its SPI register and pulls DRDY’ low. ...
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... Exception: The recalibration command ‘b’ returns an acknowledgement immediately rather than just before the actual recalibration. lQ © Quantum Research Group Ltd. Commands that return data do not send back a command echo. If desired, the command can be verified via the 'l' (lowercase L) echo function; see page 28. ...
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... Put command(s) in order to force the copy of eeprom data into Flash. See Section 4.6. lQ © Quantum Research Group Ltd. 5.1 Direction Commands Setup commands can be used to either send control information to the part for programming into its internal eeprom extract the current setting of this information. ...
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... The second byte is a binary column number from 0..7. This command also affects scope for single-key commands. lQ © Quantum Research Group Ltd. 5.3 Status Commands Status commands cause the sensor to report back information related to keys and their signals. ...
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... Higher bits (‘u’) report as 0's and are not used. This command can be used as a general 1-byte status response; if one or more bits are set, the host can take interrogate further to narrow down specifics, such as which key is being touched or in error, via other commands. lQ © Quantum Research Group Ltd. C < > OUNTS SP ...
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... The bitfields for a single column (Y) are © Quantum Research Group Ltd. The bitfields for a global response are Returns b7 n/a n/a X7Y0 byte1 1 0x00..0x0F X7Y1 byte2 X7Y2 byte3 X7Y3 byte4 X7Y4 ...
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... Byte 1 is the first returned byte in the sequence. In all the above examples a ' bit position indicates that the key is touched; a '0' indicates no touch. lQ © Quantum Research Group Ltd. G ROUP 5.4 Setup Commands Returns Setup functions are those that alter the behavior a key or a ...
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... The dwell time can be shortened below 167ns by an external circuit as described in Section 3.9. As this parameter is common to all keys, Put and Get operations send or return only one byte, 0x01. lQ © Quantum Research Group Ltd YSTERESIS ^F X Returns 0x01 ...
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... Get Section 2. Ctrl-J. In Put mode, sets the detect integrator limit for one or more keys according to scope. lQ © Quantum Research Group Ltd. The unit of measure is a burst, i.e. a setting of 5 means that a R ATE detection must be sensed 5 bursts in sequence. A burst for a Returns key occurs once every complete matrix scan ...
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... The error band can be used to detect circuit faults as well as extremes of temperature or moisture on the circuitry. Typical values are from (20% to 40%). lQ © Quantum Research Group Ltd. Special condition: If the value is set to zero, this feature is disabled. ^O 0x0F - N ...
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... Quantum Research Group Ltd. Due to the large number of bytes written to eeprom by this command, there is a significant delay from the second byte until the return echo is sent back to the host. ...
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... Bytes / Cmd # Bytes Rtnd n/a n/a Put n/a 1 Get Section 3. Uppercase 'W'. This get-only command returns the part signature as follows: 0x20 (32 decimal) - for QT60325 0x30 (48 decimal) - for QT60485 0x40 (64 decimal) - for QT60645 There is no put version of this command. Z 0x5A - E S NTER LEEP Scope Bytes / Cmd ...
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... A change in this parameter only has effect after a reset or recalibration of all keys. Valid values are from 0 to 255 decimal. In Get mode this function returns the current ^V value. lQ © Quantum Research Group Ltd. C1, MSB ^W Returns 0x00..0x7F 0x14 ...
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... K 0x4B report touches for group get indication of all touched keys © Quantum Research Group Ltd. Put Mode Operand P/G Scope Bytes/Put Range Returns ...
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... Locked reference values, step 10%. Zero disables. tolerable negative reference deviation with respect to ^O 0x0F Neg error band Locked reference values, step 1%. Zero disables. ^P 0x10 Key suppression adjacent key suppression feature © Quantum Research Group Ltd. Put Mode Operand P/G Scope Bytes/Put Range P 0x04 ...
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... C1, MSB ^U 0x15 Boundary C1 LSB boundary equation constant, C1, LSB ^V 0x16 Boundary C2 boundary equation constant, C2 noise sync enable 0x17 Noise sync device must be reset to take effect © Quantum Research Group Ltd. Put Mode Operand P/G Scope Bytes/Put Range Returns 0x00..0xFF 0x44 ...
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... Quantum Research Group Ltd. processing time. When this happens, burst timing and host communications can slow down and become erratic. Burst spacings should be verified on an oscilloscope during development to be certain that the device timings are preserved and are constant. If not, the burst length and/or pulse spacing should be reduced. Pulse Spacing = 4µ ...
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... XSD.OE = !(XS # X7); "clamp the delay cap when all 'x' lines are 0 YGG.COM =!(YG & !XSD); "Enable the 3251 so long as both Yg is high AND xsd is low "As soon as xsd goes high, disable the 3251 lQ © Quantum Research Group Ltd. Feed_Pin ) Feed_Pin ) Feed_Pin ) Feed_Pin ) Feed_Pin ) ...
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... Parameter Description Tdr delay from response T 3 Multi-byte return spacing DR Tcm Host command space SPI Clock rate Fck Tradc ADC delay from R2R setup lQ © Quantum Research Group Ltd. Min Typ Max Units 0.8 2.2 0.6 Vdd-0.7 ± 120 kohms Min ...
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... Setup - put (affect 64 keys) Lock reference Level (L) Calibrate command (all keys) Get key errors (E), Get keys pushed All other commands Preliminary Data: All specifications subject to change lQ © Quantum Research Group Ltd. Burst Spacing 250µs 300µs 400µs 10ms 10ms ...
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... Inches Min Max Notes 0.386 0.394 SQ 0.458 0.478 SQ 0.003 0.008 0.018 0.030 0.002 0.006 - 0.047 0.012 0.018 0.031 0.031 BSC 0.315 0.315 BSC 0 7 Marking QT60325-S QT60485-S QT60645-S QT60325-AS QT60485-AS QT60645-AS www.qprox.com QT60xx5 / R1.05 ...
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... F fast-recalibration field flow, 4 function summary table gate dwell dwell 12, 13, 14, 16, 25 get command, 20 ground plane © Quantum Research Group Ltd. H hard reset, 8 hysteresis, 6, 25, 26 intra-burst pulse spacing, 12, 27 jfet key design, 5 key numbering convention, 21 ...
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... R r2r ladder ladder DAC recalibrate keys (command), 28 recalibration 13, 23, 24, 26, 28, 30 reference level 25, 26, 27 reference levels, 22 reference window boundary, 8 reset 13, 14, 15, 20, 21, 28, 29, 30, 35 resonator, 14, 15 response delays, 17, 37 ...
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... Notes - © Quantum Research Group Ltd. QT60xx5 / R1.05 ...
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... Tel: +44 (0)23 8056 5600 Fax: +44 (0)23 8045 3939 This device expressly not for use in any medical or human safety related application without the express written consent of an officer of the company. © Quantum Research Group Ltd. Corporate Headquarters 1 Mitchell Point Ensign Way, Hamble SO31 4RF Great Britain admin@qprox ...