MAX951EUA+

Overview

The MAX951EUA+ is a micropower, single-supply analog device integrating an operational amplifier, comparator, and precision reference within an 8-pin μMAX package. It operates from a supply voltage range of 2.4V to 7V with a typical supply current of 7μA. The op amp is unity-gain stable with a gain bandwidth product of 20kHz and a slew rate of 12.5V/ms. The comparator features internal hysteresis and rail-to-rail output capabilities. Input bias currents are typically 5nA, ensuring minimal loading on high-impedance sources.

Feature Summary

• Integrates micro-power op amp, comparator, and 1.2V bandgap reference in an 8-pin μMAX package
• Ultra-low power consumption with 7μA typical supply current for the MAX951 variant
• Rail-to-rail input and output stages allowing operation near supply rails
• Internal ±3mV comparator hysteresis ensures clean switching with slow-moving signals

Applications

• Battery-powered portable instruments and terminals
• Low-frequency local-area alarms and detectors
• Photodiode preamplifiers for sensor interfaces
• Smart card applications requiring low power
• Infrared receivers for remote control systems

Procurement Notes

Verify the specific suffix 'EUA+' corresponds to the -40°C to +85°C temperature range and the 8-pin μMAX package configuration. Confirm RoHS compliance status as indicated by the '+' suffix. Ensure the ordering part number matches the exact functional variant required, as the MAX951 family includes distinct op amp stability options.

Selection Notes

Select the MAX951EUA+ when unity-gain stability is required for the operational amplifier section. This variant includes an internal 1.2V ±2% bandgap reference connected to the comparator's inverting input. Compare against MAX953 or MAX954 if the reference is unnecessary or if higher bandwidth (125kHz) and decompensated stability for gains of 10V/V or greater are needed.

Part Context

The MAX951EUA+ belongs to the MAX951–MAX954 family of ultra-low-power, single-supply devices manufactured by Analog Devices / Maxim Integrated. These components are designed to extend battery life in portable instruments while adding functionality in power-limited industrial controls. The family combines standard analog building blocks into a compact footprint suitable for space-constrained designs.

Replacement Considerations

Direct replacements within the same family include MAX951ESA+ (SO package) and MAX951EPA+ (Plastic DIP). Verify that the alternative package maintains the required thermal dissipation characteristics and physical footprint compatibility for the existing board layout.

FAQ

What is the common-mode input voltage range for the op amp and comparator?

The common-mode input voltage range extends from the negative supply rail (VSS) to within 1.6V of the positive rail (VDD).

Does the MAX951EUA+ include an internal reference?

Yes, the MAX951 includes an internal 1.2V ±2% bandgap reference which is connected to the inverting input of the comparator.

How does the MAX951 op amp differ from the MAX952 op amp regarding stability?

The MAX951 op amp is internally compensated to be unity-gain stable, whereas the MAX952 op amp is decompensated and stable only for gains of 10V/V or greater.