AT42QT1244-MUR

Overview

The AT42QT1244-MUR is a 24-key capacitive touch sensor IC from Microchip Technology's QMatrix series. It utilizes patented transverse charge-transfer technology with frequency hopping for robust sensing. The device supports up to 24 keys via an I2C interface operating at speeds up to 400 kHz. It operates on a supply voltage of 3V to 5V and features self-calibration, auto drift compensation, and noise filtering. The MUR suffix indicates the component is packaged in a 32-pin 5x5 mm VQFN (VFQFN) format suitable for surface mount applications.

Feature Summary

• Supports matrix layouts with up to 24 keys using transverse charge-transfer sensing technology
• Includes FMEA compliant design features and IEC/EN/UL60730 safety compliance
• Features Adjacent Key Suppression (AKS) and detection integrators for noise resistance
• Provides individual key sensitivity settings and debug output capabilities

Applications

• Domestic appliances requiring safety-critical touch controls
• Industrial control panels needing EMC resilience
• Consumer electronics with mixed key sizes and shapes

Procurement Notes

Verify the ordering suffix matches the required package type; the MUR suffix denotes the 32-VQFN (5x5) reel packaging. Confirm RoHS3 compliance status as per the latest manufacturer documentation. Ensure the host system supports I2C slave mode communication at the specified data transfer speeds before finalizing procurement.

Selection Notes

Select this model when a matrix configuration with up to 24 independent keys is required. It is suitable for designs needing FMEA analysis support and EN 60730 compliance. Consider the 32-VQFN package if board space constraints favor a 5x5 mm footprint over the TQFP option. Ensure the application environment allows for the necessary PCB layout guidelines regarding ground planes and trace lengths.

Part Context

The AT42QT1244 belongs to the Atmel/Microchip QT1244 family of digital burst mode charge-transfer sensors. It is designed specifically for matrix layout touch controls, distinguishing itself from single-channel or slider-focused models like the AT42QT1010. The device integrates all signal processing functions necessary for stable sensing under varying conditions.

Replacement Considerations

The AT42QT1245-AUR is a compatible alternative within the same family offering similar functionality but housed in a 32-TQFP package. Verify pin compatibility and software configuration requirements when substituting between the VQFN and TQFP variants.