AD7879-1WACPZ-RL

Overview

The AD7879-1WACPZ-RL 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 programmable conversion parameters. It includes auxiliary inputs for temperature sensing, battery monitoring, and GPIO functions. The component is qualified for automotive applications under AEC-Q100 standards and is housed in a 16-lead LFCSP package.

Feature Summary

• I²C-compatible serial interface with up to 400 kHz clock speed
• 12-bit resolution with 105 kSPS throughput rate
• Integrated median and averaging filters for signal processing
• Automotive qualification (AEC-Q100) and -40°C to +85°C operating range

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 suffix 'RL' indicates reel packaging when sourcing. Confirm the '1' designation ensures I²C compatibility rather than SPI. Check current availability status as automotive-grade components may have restricted distribution channels or longer lead times compared to commercial variants.

Selection Notes

Select this model over the standard AD7879W if an I²C interface is required instead of SPI. Ensure the host system supports the I²C timing specifications, specifically the 400 kHz maximum clock frequency. Verify that the 1.6 V minimum supply voltage aligns with the target application's power architecture.

Part Context

This part belongs to the AD7879 family of low-voltage touch screen controllers. The 'AD7879-1W' variant specifically denotes the I²C interface version, distinguishing it from the 'AD7879W' which uses SPI. The 'ACPZ' suffix identifies the 16-lead LFCSP package, while 'RL' specifies the reel packaging format for automated assembly.

Replacement Considerations

The AD7879WACPZ-RL serves as a functional replacement if the host controller supports I²C, though the standard AD7879W requires SPI. Direct pin-for-pin substitution with other series members like the AD7873 requires verification of interface compatibility and register mapping differences.