AD8403ARU100

Overview

The AD8403ARU100 is a quad-channel, 256-position digital potentiometer from Analog Devices. It features four independent variable resistors with a nominal resistance of 100 kΩ and a linear taper. The device operates on a single supply voltage ranging from 2.7 V to 5.5 V and utilizes an SPI-compatible 3-wire serial interface for data input. Each channel includes a volatile latch to store the wiper position, allowing for power-down retention of settings upon reactivation. The component is housed in a 24-lead TSSOP surface-mount package and supports daisy-chaining via a serial data output pin.

Feature Summary

• Quad-channel configuration with four independent 100 kΩ variable resistors
• 256-position resolution controlled via SPI-compatible 3-wire serial interface
• Low power shutdown mode consuming less than 5 μA
• Daisy-chain capability through dedicated serial data output (SDO) pin

Applications

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

Procurement Notes

Verify the specific ordering suffix against the manufacturer's current datasheet to confirm package type and tolerance. The 'RU' designation indicates a TSSOP package, while the '100' suffix specifies the 100 kΩ resistance value. Ensure compatibility with the required operating temperature range of -40°C to +125°C for industrial applications.

Selection Notes

Select this component when a quad-channel digital solution is required for precise resistance adjustment. The 100 kΩ value suits high-impedance signal paths. Consider the volatile memory nature, which requires state restoration after power loss. The 24-lead TSSOP package offers space savings compared to PDIP options but requires appropriate PCB footprint design for surface mount assembly.

Part Context

This part belongs to the AD8400/AD8402/AD8403 family of digital potentiometers. While the AD8400 provides a single channel and the AD8402 provides dual channels, the AD8403 integrates four channels into one package. All variants share similar electrical characteristics, including the 256-position resolution and SPI interface, differing primarily in channel count and package pinout.

Replacement Considerations

Direct replacements within the same family include other AD8403 variants with different resistance values or packages, such as AD8403ARZ100 for a SOIC-24 package. Cross-family replacements like the AD5253 offer non-volatile memory but differ in interface protocol and resolution.