Atmel AT42QT1085 Eight-key QTouch Touch Sensor IC DATASHEET Features QTouch Sensor Channels Up to eight keys Integrated Haptic Engine Haptic events may be triggered by touch detection or controlled by a host microcontroller over SPI Data Acquisition QTouchADC key measurement/touch detection method Configurable measurement timing and averaging Spread spectrum charge transfer Raw data from channel measurement can be read over the SPI interface GPIO Pins 12 dedicated bi-directional GPIO pins, plus up to 4 additional pins (replacing keys) Configurable as software PWM Drive, digital inputs or outputs Device setup Device configuration may be stored in NVRAM Operation Power-On reset and brown-out detection Internal calibrated oscillator Key Outline Sizes 6 mm 6 mm or larger (panel thickness dependent) widely different sizes and shapes possible, including solid or ring shapes Key Spacing 7 mm or more, center to center (panel thickness dependent) Layers required One Electrode Materials: Etched copper, silver, carbon, ITO Electrode Substrates: PCB materials polyamide FPCB PET films, glass Panel materials: Plastic, glass, composites, painted surfaces (low particle density metallic paints possible) Panel Thickness: Up to 10 mm glass, 5 mm plastic (electrode size dependent) Key Sensitivity: Individually configured over SPI interface Signal Processing: Self-calibration, auto drift compensation, noise filtering Patented Adjacent Key Suppression (AKS ) technology to ensure accurate key detection Interface: Master/Slave SPI interface, up to 750 kHz Object-based communications protocol Power: 2.0 V to 5.5 V Packages: 32-pin 5 5 mm QFN RoHS compliant 32-pin 7 7 mm TQFP RoHS compliant 9625DAT4205/20131. Pinout and Schematic 1.1 Pinout Configuration 30 27 32 31 29 28 26 25 GPIO0 1 24 KEY1 GPIO1 2 23 KEY0 GPIO2 3 22 KEY7 / GPIO12 VDD 4 21 VSS AT42QT1085 VSS 5 20 GPIO9 GPIO3 6 19 KEY6 / GPIO13 GPIO4 7 18 AVDD GPIO5817 SCK 9 10 11 12 13 14 15 16 AT42QT1085 DATASHEET 2 9625DAT4205/2013 GPIO6 GPIO11 GPIO7 GPIO10 GPIO8 CHANGE HAPTIC EN RESET HAPTIC PWM KEY5 / GPIO14 SS KEY4 / GPIO15 MOSI KEY3 MISO KEY2