AT42QT1110-MUR

Overview

The AT42QT1110 is a digital burst mode charge-transfer capacitive sensor driver supporting up to 11 QTouch channels. It operates on a 3 V to 5.5 V supply and features full-duplex SPI slave communication at speeds up to 1.5 MHz. The device supports 11-key sensing or 7-key mode with discrete PWM detect outputs. Key acquisition can be triggered by an internal clock or an external SYNC signal. It includes self-calibration, auto drift compensation, noise filtering, and patented Adjacent Key Suppression technology for stable performance under varying environmental conditions.

Feature Summary

• Patented spread-spectrum charge-transfer technology suppresses external noise and RF emissions
• Configurable discrete detect outputs provide individual key touch indication in 7-key mode
• Integrated signal processing includes self-calibration, auto drift compensation, and noise filtering
• EEPROM storage allows device configuration settings to persist across power cycles

Applications

• Consumer electronics such as televisions and media players
• Industrial control panels requiring robust capacitive input
• Appliances with plastic, glass, or composite panel interfaces

Procurement Notes

Verify the specific package variant (QFN or TQFP) against the ordering suffix. Confirm RoHS compliance status if required by your manufacturing standards. Ensure the source document matches the official Microchip datasheet identifier 9520J–AT42–05/2013 to guarantee accurate pinout and electrical specifications.

Selection Notes

Select the 11-key mode for maximum channel density where host processing handles key detection. Choose the 7-key mode with discrete outputs if hardware debouncing and direct LED driving are preferred. Consider panel thickness and material when determining electrode size and sample capacitor values to ensure optimal sensitivity and moisture tolerance.

Part Context

This component belongs to the Atmel AT42QT1110 family of QTouch capacitive sensor drivers. It is designed as a versatile solution for touch-key applications, offering both standalone operation via detect outputs and complex system integration through SPI. The device replaces mechanical switches in environments requiring sealed or aesthetic interface designs.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Verify compatibility with existing firmware and hardware layouts before considering alternative capacitive sensor controllers from other manufacturers.