AD8403AR50

Overview

The AD8403AR50 is a quad-channel, 256-position digital potentiometer from Analog Devices. It features four independent variable resistors with a nominal resistance of 50 kΩ and a linear taper. The device operates on a single supply voltage ranging from 2.7 V to 5.5 V and utilizes a 3-wire SPI-compatible serial interface for data input. Each channel includes an 8-bit latch to store the wiper position, allowing for programmable resistance between the A and B terminals. The component supports power shutdown modes with current consumption below 5 μA and is qualified for automotive applications.

Feature Summary

• Quad-channel configuration with four independent 50 kΩ variable resistors
• 256-position resolution controlled via 3-wire SPI-compatible serial interface
• Single-supply operation range of 2.7 V to 5.5 V
• Power shutdown mode reduces supply current to less than 5 μA

Applications

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

Procurement Notes

Verify the specific package type (SOIC-24 or TSSOP-24) associated with the AR suffix against the manufacturer's ordering guide, as pinout and thermal characteristics differ. Confirm RoHS compliance status for the specific manufacturing lot, as historical revisions may vary. Ensure design-in compatibility with the required serial clock rates and logic voltage levels for the target application environment.

Selection Notes

Select this component when four independent digital potentiometers are required in a single package. The 50 kΩ resistance value offers a balance between bandwidth and noise performance compared to lower or higher resistance options. Consider the SOIC-24 or TSSOP-24 package availability based on PCB space constraints. Verify that the volatile memory architecture suits the application, as settings are lost upon power loss unless retained by external means.

Part Context

The AD8403AR50 belongs to the AD840x family of digital potentiometers, which also includes the single-channel AD8400 and dual-channel AD8402. This family shares common architectural features such as the 8-bit resolution, SPI interface, and low-power shutdown capabilities. The 'AR' designation typically indicates a surface-mount package variant, while the '50' specifies the 50 kΩ nominal resistance value within the available 1 kΩ, 10 kΩ, 50 kΩ, and 100 kΩ options.

Replacement Considerations

Direct replacements include other AD8403 variants with different resistance values (AD8403AR10, AD8403AR1, AD8403AR100) if the resistance requirement can be adjusted. For non-quad channel needs, the AD8402 or AD8400 may serve as alternatives. Cross-family replacements from other manufacturers require verification of pin compatibility, serial protocol support, and electrical specifications.