AD7877WACPZ-REEL7

Overview

The AD7877WACPZ-REEL7 is a 12-bit successive approximation analog-to-digital converter (ADC) designed for touch screen digitizer applications. It integrates a synchronous serial interface, low on-resistance switches for driving touch screens, and an automatic conversion sequencer. The device operates from a single 2.7 V to 5.25 V supply with a throughput rate of 125 kSPS. Key integrated features include an on-chip 2.5 V reference, an 8-bit DAC, three auxiliary analog inputs, two direct battery measurement channels, and an on-chip temperature sensor. It supports shutdown mode with maximum current consumption of 1 µA.

Feature Summary

• Integrated 4-wire touch screen interface with dedicated X+/- and Y+/- pins
• On-chip 2.5 V reference and 8-bit DAC for LCD backlight or contrast control
• Two direct battery measurement channels supporting 0.5 V to 5 V input range
• LCD noise reduction via STOPACQ pin controlling the ADC acquisition phase

Applications

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

Procurement Notes

Verify the specific package type against the datasheet outline dimensions. The 'W' suffix indicates the Wafer Level Chip Scale Package (WLCSP), while 'ACPZ' typically denotes the Lead Frame Chip Scale Package (LFCSP). Confirm that the REEL7 suffix matches the required tape and reel quantity for manufacturing integration.

Selection Notes

Select this component when a high-speed 12-bit ADC with integrated touch screen drivers is required. Ensure the system voltage falls within the 2.7 V to 5.25 V range. Consider the WLCSP package constraints if board space is limited, noting the 2.5 mm x 2.8 mm footprint compared to the larger LFCSP option.

Part Context

This part belongs to the AD7877 family of touch screen controllers. It is functionally similar to the AD7877ACPZ but utilizes a different packaging technology. The WLCSP variant offers a smaller form factor suitable for dense portable electronics layouts.

Replacement Considerations

The AD7877ACPZ is a direct functional alternative using the LFCSP package. Verify pin compatibility and thermal requirements when substituting between WLCSP and LFCSP packages.