MAX5421BEUB+T

Overview

The MAX5421BEUB+T is a digitally programmable precision voltage divider optimized for programmable gain amplifier (PGA) configurations. It provides four noninverting gain ratios of 1, 2, 4, and 8 via a two-bit parallel interface. The device features a resistor ratio accuracy of ±0.09% and includes an on-chip matching resistor for op amp bias-current compensation. It operates from a single +5V or dual ±5V supply with a typical supply current of 3µA. The end-to-end resistance is 15kΩ, and the output impedance at W is 8kΩ for gains greater than 1. It is housed in a 10-pin µMAX package and specified over the -40°C to +85°C temperature range.

Feature Summary

• Four precision noninverting gain ratios: 1, 2, 4, and 8
• ±0.09% divider ratio accuracy guaranteed over -40°C to +85°C
• On-chip matching resistor for op amp bias-current compensation
• Low 3µA supply current with CMOS/TTL compatible 2-wire parallel interface

Applications

• General-purpose programmable noninverting amplifiers
• Programmable instrumentation amplifiers

Procurement Notes

Verify the component authenticity by checking the manufacturer markings against the official datasheet specifications. Confirm the ordering suffix matches the required accuracy grade (+B indicates ±0.09%) and package type (UB indicates 10-pin µMAX). Ensure the operating environment stays within the specified -40°C to +85°C temperature range to maintain performance guarantees.

Selection Notes

Select the MAX5421BEUB+T when PGA applications require precise gain switching with minimal power consumption. The inclusion of the matching resistor makes it suitable for direct connection to operational amplifiers without external offset compensation components. Choose this part over the MAX5420 if bias-current compensation is needed, and ensure the system supports the required ±0.09% accuracy tolerance.

Part Context

This component belongs to the MAX5420/MAX5421 family of digitally programmable voltage dividers. The MAX5421 variant specifically integrates a matching resistor not present in the MAX5420. The 'B' suffix denotes the ±0.09% accuracy class, distinct from the higher precision 'A' (±0.025%) or lower precision 'C' (±0.5%) variants. The 'UB' suffix specifies the 10-lead µMAX surface-mount package.

Replacement Considerations

Direct functional replacements include other members of the MAX542x family such as the MAX5421AEUB+T for higher accuracy or MAX5421CEUB+T for cost-sensitive applications. For systems requiring only three gain steps or lacking the need for bias compensation, the MAX5420 series may be considered if the matching resistor pins are left unconnected.