AD7889-1ACBZ-RL

Overview

The AD7889-1ACBZ-RL is a 12-bit successive approximation analog-to-digital converter (SAR ADC) designed for resistive touch screen applications. It operates on a single 1.6 V to 3.6 V supply and supports an I²C interface, indicated by the '-1' suffix in the model number. The device features a throughput rate of 105 kSPS and includes a preprocessing block with median and averaging filters to reduce noise. Key specifications include a maximum shutdown current of 6 μA, an auxiliary input/battery monitor range of 0.5 V to 5 V, and integrated temperature sensing. It is housed in a 12-ball WLCSP package.

Feature Summary

• 12-bit SAR ADC with 105 kSPS throughput rate
• I²C serial interface (AD7889-1 variant)
• Median and averaging filter for noise reduction
• Auxiliary input/battery monitor (0.5 V to 5 V)
• Shutdown mode with <6 μA current consumption

Applications

• Personal digital assistants
• Smart handheld devices
• Touch screen monitors
• Point-of-sale terminals
• Medical devices

Procurement Notes

Verify that the specific ordering suffix 'ACBZ-RL' corresponds to the WLCSP package and I²C interface as defined in the official Analog Devices ordering guide. Confirm that the '-1' designation aligns with the required I²C communication protocol rather than SPI. Ensure compatibility with the host system's voltage levels and address configuration requirements.

Selection Notes

Select this component when an I²C interface is required for touch screen digitization. The AD7889-1 variant differs from the standard AD7889 by utilizing SDA/SCL pins instead of DOUT/DIN/CS for serial communication. Consider the 12-ball WLCSP package constraints for board space. Verify that the 1.6 V to 3.6 V operating voltage range matches the system power supply.

Part Context

The AD7889-1ACBZ-RL belongs to the AD7879/AD7889 family of low-voltage touch screen controllers. The AD7889 is functionally identical to the AD7879 but offers a backside-coated WLCSP option for improved reliability. The '-1' suffix specifically denotes the I²C-compatible interface version, distinguishing it from the SPI-based AD7879/AD7889 models.

Replacement Considerations

The AD7879-1ACPZ-RL serves as a pin-compatible alternative if an LFCSP package is preferred over the WLCSP form factor. Both variants share the same electrical characteristics and functionality, differing only in the physical package type.