QT60485 QUANTUM [Quantum Research Group], QT60485 Datasheet
![no-image](/images/no-image-200.jpg)
QT60485
Related parts for QT60485
QT60485 Summary of contents
Page 1
... 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 ...
Page 2
Quantum Research Group Ltd. Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
Page 3
Table 1.1 Device Pin List Pin Name Type Description Master-Out / Slave In SPI line. In Master/Slave SPI mode is used for both communication directions. 1 MOSI I Slave SPI mode is the data input (in only). Master-In ...
Page 4
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 ...
Page 5
Figure 1-5 QT60xx5 Basic Circuit Model X drive X drive ( line ( line electrode electrode electrod e ...
Page 6
Larger absolute values of threshold desensitize keys since the signal must travel farther in order to cross the threshold level. Conversely, lower thresholds make keys more sensitive and Cs drift, the reference point ...
Page 7
Only a full recalibration via a reset or a recalibration command will perform a complete recalibration involving both the R2R Offset and Cz capacitors (Section 2.10). After a fast recalibration has taken place, the affected key will once ...
Page 8
Cz and DAC offset values to alter key is outside of a limit, either of bits 2 and 3 of command 'e' will be set for that ...
Page 9
... 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) ...
Page 10
Quantum Research Group Ltd. 10 www.qprox.com QT60xx5 / R1.05 ...
Page 11
Quantum Research Group Ltd. 11 www.qprox.com QT60xx5 / R1.05 ...
Page 12
Figure 3-3 Relationship of X and Y signals ' 3.4 OISE ...
Page 13
Section 5.7. Conversely longer spacings permit higher burst lengths but slow down response time. Spacings from 250µs to 2ms are available. 3.9 PLD Circuit and Charge Sampler The PLD should be a CMOS 22V10 type having no internal ...
Page 14
The rated resistance of an R2R ladder is also its Thevenin equivalent resistance which affects the scaling of the offset injected into the amplifier, in terms of mV/bit. The scaling of offset injection also affects the crossover points for the ...
Page 15
External fields can cause interference leading to false detections or sensitivity shifts. Most fields come from AC power sources. RFI noise sources are heavily suppressed by the low impedance nature of the QT circuitry itself. External noise becomes a problem ...
Page 16
ESD / Noise Considerations In general the QT60xx5 will be well protected from static discharge during use by the overlying panel. However, even with a dielectric panel transients currents can still flow into scan lines via induction or in ...
Page 17
T cm DRDY {from sensor} SS {from host} SCK {from host} MOSI {from host} Host Command Byte 1 MISO {from sensor} Invalid Data T ...
Page 18
Figure 4-4 Filtering SPI Slave-Only Connections +5 QT60xx5 Circuit 10K X drives DRDY 220 shown) SS 47pF Ca SCK Ca MISO Y Lines MOSI 100 shown) 22pF Ca RESET 1nF Figure 4-5 ...
Page 19
In Master mode the sensor asserts control over this line, to make the host a slave and to frame the data. This line must idle high; the part includes an internal pullup resistor and should be floated during idle times. ...
Page 20
Commands & Functions The command structure is designed to minimize control and data traffic. All repetitive data and status commands from the host are single-byte, and most commands result in single- byte device responses. Behavioral setup commands involve multiple ...
Page 21
Scope Commands The host should always set the scope parameter when initializing the part during normal operation as well as during setup. Scope commands are persistent and apply to all subsequent functions that are affected by scope, until a ...
Page 22
ETECTION NTEGRATOR Scope Bytes / Cmd # Bytes Rtnd n/a n/a Put 1 1 Get Numeric '5'. Returns the Detection Integrator counter value for one key whose location is determined by scope. This ...
Page 23
RROR ODE FOR ELECTED Scope Bytes / Cmd # Bytes Rtnd n/a n/a Put 1 1 Get Section 2.12 Lowercase 'E'. Returns the error byte for a selected key defined ...
Page 24
OUCH EPORTING FOR Scope Bytes / Cmd # Bytes Rtnd n/a n/a Put Get Section 2.12 Uppercase 'K'. Returns bytes depending on ...
Page 25
EGATIVE HRESHOLD Scope Bytes / Cmd Byte 2 Range 64 2 Put 64 1 Get Section 2. Ctrl-C. In Put mode, the command followed by a setting is programmed into eeprom ...
Page 26
EGATIVE RIFT OMPENSATION Scope Bytes / Cmd Byte 2 Range Put 1 1 Get Section 2. Ctrl-H. In Put mode, sets the rate of drift compensation ...
Page 27
Special condition: If the value for ^L is set to zero this feature is disabled and the key will never auto-recalibrate after a prolonged touch. ^M 0x0D - NTRA URST ULSE Scope Bytes / Cmd Byte ...
Page 28
Supervisory / System Functions Supervisory functions report or control miscellaneous functions that affect overall chip control, testing, or diagnostics. All supervisory functions ignore scope except where noted. For commands requiring Put mode to operate, the device should be set ...
Page 29
... 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 2nd Byte Range ...
Page 30
OUNDARY QN ONSTANT Scope Bytes / Cmd Byte 2 Range 64 2 Put 64 1 Get Section 2. Ctrl-T. In Put mode, sets the MSB of equation constant C1 for boundary checking ...
Page 31
Function Summary Table Char Hex Name Description Direction Commands g 0x67 Get all subsequent Setups become 'Gets' p 0x70 Put all subsequent Setups become 'Puts’ Scope Commands s 0x73 Set one key scope targets a specific key in range ...
Page 32
Char Hex Name Description Setup Commands touch sensitivity threshold; less = more ^A 0x01 Negative threshold 4,5,6,7,8,10,12,15,17,20,25,30,35,45,55,64 counts sensitivity to positive signals for recalibration ^B 0x02 Positive threshold 4,5,6,7,8,10,12,15,17,20,25,30,35,45,55,64 counts hysteresis for negative threshold ^C 0x03 Negative hysteresis 50%, 25%, ...
Page 33
Char Hex Name Description Supervisory Commands 6 0x36 Eeprom checksum returns checksum of internal eeprom sends operand to R2R DAC; byte 2 must be sent within D 0x44 DAC test 100ms of command byte locks reference levels into eeprom for ...
Page 34
Timing Limitations The device requires processing time between bursts, as well as time to handle communications with the host. With short burst spacings, long burst lengths, and long intra-burst pulse spacings, the device can simply run out of available ...
Page 35
PLD Source Listing Pre-programmed parts are available from Quantum in small quantities. The object code file for this PLD is also available upon request. TITLE 'E664SPI' Description Timing skew generator for E664SPI matrix board. Code is for ICT PEEL22CV10AZ ...
Page 36
Electrical Specifications 7.1 Absolute Maximum Specifications Operating temp ...
Page 37
Maximum Drdy Response Delays ... with adjacent key suppression disabled: Function Type Setup - put (affect 1 key) Setup - put (affect 8 keys) Setup - put (affect 64 keys) Lock reference Level (L) Calibrate command (all keys) Get ...
Page 38
... 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 ...
Page 39
Index A adc subranging adjacent key suppression alert output, 15 application assistance block diagram, 5 boundary equation, 30, 33 burst length 12, 20, 24, 25, 28, 34 burst spacing, 6, 25, ...
Page 40
... 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 ...
Page 41
Notes - © Quantum Research Group Ltd. QT60xx5 / R1.05 ...
Page 42
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 ...