AD8403ARUZ100

Overview

The AD8403ARUZ100 is a quad-channel, 8-bit digital potentiometer from Analog Devices. It provides four independent variable resistors with 256 tap positions in a 24-lead TSSOP package. The nominal resistance is 100 kΩ with a ±1% channel-to-channel matching tolerance and a temperature coefficient of 500 ppm/°C. It operates on a single supply voltage ranging from 2.7 V to 5.5 V. The device uses an SPI-compatible 3-wire serial interface for data input and includes a shutdown mode that reduces current consumption to less than 5 μA.

Feature Summary

• Quad-channel configuration with 256-position resolution
• SPI-compatible 3-wire serial interface with daisy-chain capability via SDO pin
• Low power shutdown mode consuming less than 5 μA
• Extended industrial temperature range from -40°C to +125°C

Applications

• Mechanical potentiometer replacement
• Programmable filters, delays, and time constants
• Volume control and panning
• Line impedance matching
• Power supply adjustment

Procurement Notes

Verify the specific suffix 'U' indicates the TSSOP-24 package and 'Z' denotes RoHS compliance when sourcing. Confirm the '100' suffix corresponds to the 100 kΩ resistance value. Check for automotive qualification requirements if applicable to the design environment.

Selection Notes

Select this component for designs requiring four digitally controlled variable resistors in a compact surface-mount package. Ensure the system logic levels are compatible with the 2.7 V to 5.5 V operating range. Consider the 500 ppm/°C temperature coefficient for precision applications requiring stability over wide temperature variations.

Part Context

This part belongs to the AD8400/AD8402/AD8403 family of 1-, 2-, and 4-channel digital potentiometers. The AD8403 specifically offers four channels, distinguishing it from the single-channel AD8400 and dual-channel AD8402. All variants share similar electrical characteristics and interface protocols.

Replacement Considerations

Direct replacements within the same family include other AD8403 variants with different resistance values or packages. Cross-family alternatives like the AD5124 offer non-volatile memory but differ in architecture and interface requirements.

FAQ

What is the function of the SHDN pin?

The SHDN pin forces the resistor to an end-to-end open-circuit condition on the A terminal and shorts the wiper to the B terminal, achieving a microwatt power shutdown state.

How does the reset (RS) pin operate?

The active-low RS pin forces the wiper to midscale by loading the hexadecimal value 80H into the VR latch.

Is the device suitable for daisy-chaining?

Yes, the serial data output (SDO) pin allows simple daisy chaining in multiple VR applications without additional external decoding logic.