AD7879-1WACPZ-RL7

Overview

The AD7879-1WACPZ-RL7 is a 12-bit successive approximation analog-to-digital converter (SAR ADC) designed for 4-wire resistive touch screen interfaces. It operates on a single 1.6 V to 3.6 V supply and supports an I²C serial interface. The device features a throughput rate of 105 kSPS, median and averaging filters for noise reduction, and an automatic conversion sequencer. It includes auxiliary inputs for temperature sensing, battery monitoring, and GPIO functionality. The component is qualified for automotive applications under AEC-Q100 standards and operates within a temperature range of -40°C to +85°C.

Feature Summary

• 12-bit SAR ADC with 105 kSPS throughput and I²C interface
• Integrated median and averaging filters for signal processing
• Supports touch-pressure measurement and wake-up on touch function
• AEC-Q100 qualified for automotive reliability

Applications

• Automotive infotainment systems
• Smart handheld devices and personal digital assistants
• Medical devices requiring precise touch input
• Point-of-sale terminals

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current data sheet to confirm package type and reel quantity. Confirm that the I²C interface variant matches the system bus requirements. Check for any recent product change notices or end-of-life notifications from Analog Devices before finalizing procurement plans.

Selection Notes

Select this model when an I²C interface is required instead of SPI. Ensure the host microcontroller supports the I²C timing specifications provided in the datasheet. Consider the LFCSP package thermal characteristics if high ambient temperatures are expected. Verify that the 1.6 V to 3.6 V supply range aligns with the target system voltage.

Part Context

This part belongs to the AD7879 family of low-voltage touch screen controllers. The '1' in the model number indicates the I²C interface variant, distinguishing it from the SPI-based AD7879W. It shares core functional blocks like the 12-bit ADC and filter engine with other family members but differs in communication protocol and pin assignments for address configuration.

Replacement Considerations

The AD7879WACPZ-RL7 serves as a direct replacement for the AD7879-1ACPZ-RL7 in designs requiring the LFCSP package. For TSSOP packages, the AD7879-1ARUZ-RL is the equivalent form factor. Ensure software drivers are updated to support I²C addressing if migrating from SPI variants.