• Number of keys: Up to 24
• Technology: Patented charge-transfer (transverse mode), with frequency hopping Key outline sizes:  6 mm × 6 mm or larger (panel thickness dependent); different sizes and shapes possible
• Key spacings: 8 mm or wider, center to center (panel thickness dependent)
• Electrode design: Two-part electrode shapes (drive-receive); wide variety of possible layouts
• PCB Layers required: One layer (with jumpers), two layers (no jumpers)
• Electrode materials: PCB, FPCB, silver or carbon on film, ITO on film
• Panel materials: Plastic, glass, composites, painted surfaces (low particle density metallic paints possible)
• Panel thickness: Up to 50 mm glass, 20 mm plastic (key size dependent)
• Key sensitivity: Individually settable via simple commands over communication interface
• Interface: I2C (please use AT42QT1245 for SPI)
• Signal processing: Self-calibration, auto drift compensation, noise filtering, Adjacent Key Suppression® (AKS®) technology
• FMEA compliant design features
• UL approval
• VDE compliance
• For use in both class B and class C safety-critical products
• Detects and Reports Key Failure
• Power supply: +3 V to 5 V
• 32-pin 7 × 7 mm TQFP RoHS compliant
• 32-pin 5 × 5 mm QFN RoHS compliant
• IEC/EN/UL60730 (Ed. 5.1) / IEC/EN 60335 (Ed. 5.2) compliant design features for use in both class B and class C safety-critical appliance products.

The Microchip's AT42QT1244 and 1245 are a capacitive touch controllers with configurable 24-QTouch buttons. The Microchip QMatrix sensing algorithm (mutual capacitance) enables the user to achieve more buttons than there are pins because of this matrix layout. The device includes all signal processing functions necessary to provide stable sensing under a wide variety of changing conditions and frequencies. UL approval and VDE compliance IEC/EN 60730 (Ed. 5.1) / IEC/EN 60335 (Ed. 5.2) for use in both class B and class C safety-critical products.

The AT42QT1244 connects via an I2C interface while the 42QT1245 features a slave SPI port.