Y4A X3 Y4B X2 Y5A X1 Y5B X0 Vdd Vss Vss Vdd LED Y0A DRDY Y1A VREF Y2A S SYNC Y3A /SS SMP l Q QT60326, QT60486 32 & 48 KEY QMATRIX ICs z Advanced second generation QMatrix controller z Keys individually adjustable for sensitivity, response time, and many other critical parameters z Panel thicknesses to 50mm through any dielectric 44 43 42 41 40 39 38 37 36 35 34 z 32 and 48 key versions MOSI 1 33 Y3B MISO 2 32 Y2B z 100% autocal for life - no in-field adjustments SCK 3 31 Y1B z SPI Slave and UART interfaces /RST 4 30 Y0B QT60326 z Sleep mode with wake pin Vdd 5 29 Vdd QT60486 Vss 6 28 Vss z Adjacent key suppression feature XT2 7 27 Vdd z Synchronous noise suppression pin TQFP-44 XT1 8 26 X7 z Spread-spectrum modulation: high noise immunity RX 9 25 X6 TX 10 24 X5 z Mix and match key sizes & shapes in one panel WS 11 23 X4 z Low overhead communications protocol 13 15 16 18 19 20 21 12 14 17 22 z FMEA compliant design features z Negligible external component count z Extremely low cost per key z 44-pin Pb-free TQFP package APPLICATIONS - y Security keypanels y Appliance controls y ATM machines y Automotive panels y Industrial keyboards y Outdoor keypads y Touch-screens y Machine tools These digital charge-transfer (QT) QMatrix ICs are designed to detect human touch on up 48 keys when used with a scanned, passive X-Y matrix. They will project touch keys through almost any dielectric, e.g. glass, plastic, stone, ceramic, and even wood, up to thicknesses of 5 cm or 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 sizes and shapes of keys can be mixed within a single panel of keys and can vary by a factor of 20:1 in surface area. The sensitivity of each key can be set individually via simple functions over the SPI or UART port, for example via Quantums QmBtn program, or from a host microcontroller. Key setups are stored in an onboard eeprom and do not need to be reloaded with each powerup. These devices are designed specifically for appliances, electronic kiosks, security panels, portable instruments, machine tools, or similar products that are subject to environmental influences or even vandalism. It can permit the construction of 100% sealed, watertight control panels that are immune to humidity, temperature, dirt accumulation, or the physical deterioration of the panel surface from abrasion, chemicals, or abuse. To this end the device contains Quantum-pioneered adaptive auto self-calibration, drift compensation, and digital filtering algorithms that make the sensing function robust and survivable. The parts can scan matrix touch keys over LCD panels or other displays when used with clear ITO electrodes arranged in a matrix. They do not require chip on glass or other exotic fabrication techniques, thus allowing the OEM to source the matrix from multiple vendors. Materials such as such common PCB materials or flex circuits can be used. External circuitry consists of a resonator and a few passive parts, all of which can fit into a 6.5 sq cm footprint (1 sq inch). Control and data transfer is via either an SPI or UART port. These devices make use of an important new variant of charge-transfer sensing, transverse charge-transfer, in a matrix format that minimizes the number of required scan lines. Unlike older methods, it does not require one IC per key. AVAILABLE OPTIONS T Keys Part Number A 0 0 -40 C to +105 C 32 QT60326-AS-G 0 0 -40 C to +105 C 48 QT60486-AS-G L Q Copyright 2003-2005 QRG Ltd QT60486-AS R8.01/0105Contents 4.15 Return Last Command - 0x0f 1 Overview .............................. 3 .................. 16 1.1 Part differences 4.16 Internal Code - 0x10 ......................... 3 ...................... 16 1.2 Enabling / Disabling Keys 4.17 Internal Code - 0x11 .................... 3 ...................... 16 4.18 Internal Code - 0x12 2 Hardware & Functional ..................... 3 ...................... 16 2.1 Matrix Scan Sequence 4.19 Sleep - 0x16 ...................... 3 .......................... 16 2.2 Burst Paring 4.20 Data Set for One Key - 0x4k ........................... 3 .................. 16 2.3 Response Time 4.21 Status for Key k - 0x8k ......................... 4 .................... 16 2.4 Oscillator 4.22 Cal Key k - 0xck ............................ 4 ........................ 16 2.5 Sample Capacitors Saturation Effects 4.23 Command Sequencing .............. 4 ..................... 16 Table 4.2 Command Summary 2.6 Sample Resistors ........................ 4 ................... 18 2.7 Signal Levels 5 Setups .......................... 5 ............................... 20 2.8 Matrix Series Resistors 5.1 Negative Threshold - NTHR ..................... 5 ................... 20 2.9 Key Design 5.2 Positive Threshold - PTHR ........................... 6 ................... 20 2.10 PCB Layout, Construction 5.3 Drift Compensation - NDRIFT, PDRIFT ................... 6 ............. 20 2.10.1 LED Traces and Other Switching Signals 5.4 Detect Integrators - NDIL, FDIL ............ 6 ................. 21 2.10.2 PCB Cleanliness 5.5 Negative Recal Delay - NRD ....................... 6 ................... 21 2.11 Power Supply Considerations 5.6 Positive Recalibration Delay - PRD ................. 6 ............... 21 2.12 Startup / Calibration Times 5.7 Burst Length - BL ................... 6 ........................ 22 Table 2-1 Calibration Timings 5.8 Adjacent Key Suppression - AKS .................... 7 ................ 22 2.13 Reset Input 5.9 Oscilloscope Sync - SSYNC .......................... 7 ................... 22 2.14 Spread Spectrum Acquisitions 5.10 Negative Hysteresis - NHYST ................. 7 ................. 22 2.15 Detection Integrators 5.11 Dwell Time - DWELL ...................... 7 ...................... 22 2.16 FMEA Tests 5.12 Mains Sync - MSYNC .......................... 7 ..................... 22 2.17 Wiring 5.13 Burst Spacing - BS ............................. 9 ....................... 23 Table 2.2 - Pin Listing 5.14 Serial Rate - SR ....................... 9 ........................ 23 Figure 2.7 Wiring Diagram 5.15 Lower Signal Limit - LSL ...................... 10 .................... 23 5.16 LED / Alert Output - LED 3 Serial Communications ..................... 11 .................... 23 3.1 DRDY Pin 5.17 Host CRC - HCRC ............................ 11 ....................... 23 Table 5.1 Setups Block 3.2 SPI Communications ...................... 11 ....................... 24 Table 5.2 LED Function Control Byte Bits 3.3 UART Communications ..................... 12 ............... 25 Table 5.3 Key Mapping 4 Control Commands ....................... 13 ....................... 25 Table 5.4 Setups Block Summary 4.1 Null Command - 0x00 ...................... 13 .................. 26 4.2 Enter Setups Mode - 0x01 6 Specifications .................... 14 .......................... 27 4.3 Cal All - 0x03 6.1 Absolute Maximum Electrical Specifications .......................... 14 ........... 27 4.4 Force Reset - 0x04 6.2 Recommended operating conditions ....................... 14 ............... 27 4.5 General Status - 0x05 6.3 DC Specifications ...................... 14 ........................ 27 4.6 Report 1st Key - 0x06 6.4 Timing Specifications ...................... 15 ...................... 27 4.7 Report Detections for All Keys - 0x07 6.5 Mechanical Dimensions .............. 15 ..................... 27 Table 4.1 Bit fields for multiple key reporting and key 6.6 Marking ............................. 28 15 numbering ............................ 7 Appendix ............................. 29 4.8 Report Signals for All Keys - 0x08 ................ 15 7.1 8-Bit CRC Software C Algorithm ................. 29 4.9 Report References for All Keys - 0x09 .............. 15 7.2 16-Bit CRC Software C Algorithm 4.10 Report Deltas for All Keys - 0x0a ................ 29 ................ 15 7.3 1-Sided Key Layout ....................... 30 4.11 Report Error Flags for All Keys - 0x0b ............. 15 7.4 PCB Layout ........................... 30 4.12 Report FMEA Status - 0x0c .................. 15 4.13 Dump Setups Block - 0x0d ................... 15 4.14 Eeprom CRC - 0x0e ...................... 15 lQ 2 QT60486-AS R8.01/0105