AT42QT1085-AUR

Overview

The AT42QT1085-AUR is a capacitance touch sensor IC featuring eight QTouch sensor channels and an integrated haptic engine. It operates on a 2.0 V to 5.5 V supply voltage with an SPI interface supporting up to 750 kHz. The device provides twelve dedicated bi-directional GPIO pins, expandable by four additional pins through key reconfiguration. It utilizes the QTouchADC measurement method with spread spectrum charge transfer for noise immunity. The package is a 32-pin TQFP (7x7 mm) RoHS compliant variant.

Feature Summary

• Integrated haptic engine capable of triggering effects via touch detection or host microcontroller commands over SPI
• Advanced signal processing including self-calibration, auto drift compensation, and patented Adjacent Key Suppression technology
• Configurable GPIO pins functioning as digital inputs/outputs or software PWM drives with sixteen duty cycle options
• Spread spectrum operation to suppress external noise and limit RF emissions without requiring external sampling capacitors

Applications

• Consumer electronics requiring tactile feedback integration
• Industrial control panels needing robust noise immunity
• Appliances utilizing glass or plastic overlay interfaces

Procurement Notes

Verify the specific ordering suffix against official Microchip documentation to confirm package type and tape/reel specifications. Confirm current production status and lifecycle phase prior to design finalization. Ensure compatibility with existing SPI master controllers regarding voltage levels and timing requirements.

Selection Notes

Select this component when eight independent touch keys are required alongside integrated haptic feedback capabilities. The device supports single-layer electrode construction on various substrates including PCB, FPCB, and PET films. Consider the available GPIO count for system control functions if external microcontrollers need interfacing directly through the sensor IC.

Part Context

The AT42QT1085 belongs to the Atmel QTouch family of capacitive sensing solutions. It implements the QTouchADC algorithm for reliable touch detection under varying environmental conditions. The device integrates all necessary signal processing to function with minimal external components, simplifying PCB layout and reducing overall system cost.

Replacement Considerations

Check for updated revisions within the AT42QT1085 series. Verify pinout compatibility if substituting with other QTouch devices. Review datasheet differences regarding operating voltage ranges and GPIO configurations before implementation.