MAX5428EUA+

Overview

The MAX5428EUA+ is a linear-taper digital potentiometer with 32 tap positions and a nominal end-to-end resistance of 50kΩ. It operates on a single supply voltage ranging from 2.7V to 5.5V, consuming a maximum static current of 1.5µA. The device features an optional one-time programmable (OTP) function that allows the wiper's power-on reset position to be set to a user-defined value or permanently locked via serial interface disablement. It utilizes a simple 2-wire serial interface for control and is housed in an 8-pin µMAX package.

Feature Summary

• One-Time Programmable Wiper Position: Allows setting a specific power-on reset position or locking the wiper to prevent further adjustment.
• Linear-Taper Digital Potentiometer: Provides 32 discrete tap positions with a nominal 50kΩ end-to-end resistance.
• Ultra-Low Power Consumption: Operates with a maximum static supply current of 1.5µA across the full operating temperature range.
• Simple 2-Wire Serial Interface: Controls wiper position using Chip Select (CS) and Up/Down (U/D) inputs.

Applications

• Mechanical potentiometer replacement
• Products requiring one-time factory calibration
• Fixed resistor-divider applications after lock-bit programming

Procurement Notes

Verify the component is the MAX5428 variant with 50kΩ resistance, distinct from the MAX5427 (100kΩ) and MAX5429 (10kΩ). Confirm the 'EUA' suffix indicates the 8-pin µMAX package and extended temperature range (-40°C to +85°C). Ensure the OTP feature requirements align with the specific programming sequence needed for your application.

Selection Notes

Select this model when a 50kΩ digital potentiometer with 32 taps is required. Consider the OTP capability if a fixed initial state or permanent lockout is necessary. Verify that the 2-wire interface timing meets system requirements. The µMAX package is suitable for space-constrained designs compared to larger packages.

Part Context

The MAX5428EUA+ belongs to the MAX5427/MAX5428/MAX5429 family of one-time programmable, linear-taper digital potentiometers. These devices replace mechanical potentiometers by offering digital control over resistance values while maintaining similar functionality. The family shares identical pinouts and operational characteristics, differing primarily in their end-to-end resistance values.

Replacement Considerations

Direct replacements within the same family include the MAX5427EUA+ (100kΩ) and MAX5429EUA+ (10kΩ), provided the resistance value matches the circuit requirements. Other digital potentiometers may require interface and pinout compatibility checks.