AT42QT1111-AU

Overview

The AT42QT1111-AU is a digital burst mode charge-transfer capacitive sensor driver designed for touch-key applications. It supports up to 11 QTouch channels or 7 keys with individual discrete outputs. The device operates on a 1.8 V to 5.5 V supply and features full-duplex SPI slave communication at speeds up to 750 kHz. It includes self-calibration, auto drift compensation, noise filtering, and Adjacent Key Suppression technology. Configuration data is stored in internal EEPROM. The component is available in a 32-pin 7x7 mm TQFP package.

Feature Summary

• Supports up to 11 QTouch channels or 7 keys with configurable PWM detect outputs
• Features patented spread-spectrum charge-transfer technology for noise suppression
• Includes self-calibration, auto drift compensation, and Adjacent Key Suppression
• Configurable detection triggers via internal clock or external SYNC pin

Applications

• Consumer electronics such as TVs and media players
• Industrial control panels requiring robust touch interfaces
• Appliances with plastic, glass, or composite panel overlays

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to ensure correct package type and temperature rating. Confirm RoHS compliance status and moisture sensitivity level requirements for your assembly process. Check for any product change notices that may affect pinout or electrical specifications before finalizing procurement.

Selection Notes

Select this component when designing systems requiring up to 11 independent touch inputs with flexible trigger modes. Ensure the host microcontroller supports SPI communication at the required speed. Verify that the panel thickness and electrode materials are compatible with the device's sensing capabilities and calibration range.

Part Context

This part belongs to the Microchip AT42QT1xxx series of QTouch capacitive sensor controllers. It is functionally similar to the AT42QT1110 but offers additional discrete output options in 7-key mode. The AU suffix denotes the 32-pin TQFP package variant within this family.

Replacement Considerations

The AT42QT1110 is a related model within the same series. Verify pin compatibility and feature set differences, particularly regarding discrete output availability, before substituting.