Analog Devices Inc./Maxim Integrated MAX951EPA

Overview

MAX951EPA from Maxim Integrated is an ultra-low-power, single-supply analog IC integrating a unity-gain-stable op amp, comparator with internal 1.2V ±2% bandgap reference, and rail-to-rail output stages in an 8-pin PDIP package. It operates from 2.7V to 7V, draws 7μA typical supply current, supports common-mode input down to VSS, and delivers clean switching via ±3mV internal hysteresis - ideal for battery-powered smoke detectors and infrared receiver front ends.

For engineers reviewing the MAX951EPA datasheet, MAX951EPA pinout, MAX951EPA application, or MAX951EPA equivalent, key selection considerations include its integrated reference accuracy (±2% over –40°C to +85°C), rail-to-rail output swing capability, ultra-low quiescent current budget, and verified performance in high-impedance sensor preamplifier circuits with continuous monitoring requirements.

Technical Context

The MAX951EPA implements a micropower CMOS architecture combining three functional blocks: a unity-gain-stable op amp (20kHz GBW, 12.5V/ms slew rate), a comparator with internally connected REF to COMPIN−, and a buffered 1.2V bandgap reference. Its input stage supports rail-to-rail common-mode range (VSS to VDD − 1.6V) and exhibits <3pA input bias current at room temperature.

Both op amp and comparator outputs swing rail-to-rail with sourcing capability up to 40mA (COMPOUT) and 70–820μA (AMPOUT), while maintaining microamp-level quiescent operation. Internal ±3mV hysteresis ensures noise-immune digital transitions even with slow-moving inputs, eliminating need for external feedback networks in basic threshold-detection applications.

Key Specifications

Pinout & Package

MAX951EPA uses an 8-pin plastic DIP (dual in-line package) with 0.300" wide body and 0.100" lead pitch. The package is through-hole mountable, RoHS-compliant, and rated for operation from –40°C to +85°C.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar op amp + comparator + reference applications.

Compared with MAX952EPA, MAX951EPA provides guaranteed unity-gain stability and lower input noise for precision DC sensor buffering, while TLV2304IPW trades integration for flexibility and wider supply range (2.7V–16V), making it suitable where reference independence or higher voltage operation is critical.

Availability

MAX951EPA is available at Aetrix Electronics and suitable for battery-powered systems, smoke detectors and safety sensors, low-frequency local-area alarms/detectors, and infrared receivers for remote controls requiring stable component supply and long-term industrial availability.

Supply support for MAX951EPA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog and mixed-signal ICs for power, sensing, and connectivity applications, with emphasis on low-power, high-reliability solutions for industrial and safety-critical systems.

The MAX951–MAX954 family was engineered specifically for ultra-low-power, single-supply sensor signal conditioning and threshold detection in portable and battery-operated safety equipment - prioritizing integration, stability, and long-term parametric consistency over raw speed.

FAQ

What is the operating temperature range of the MAX951EPA?

The MAX951EPA is specified for operation from –40°C to +85°C. This extended industrial temperature range ensures reliable performance in smoke detectors mounted in attics or garages, outdoor alarm sensors, and consumer electronics exposed to seasonal ambient variations. All electrical characteristics - including reference voltage accuracy (±2%), input offset voltage, and supply current - are guaranteed across this full range.

Does the MAX951EPA require external components for basic comparator operation?

No, the MAX951EPA does not require external components for basic comparator operation. Its internal 1.2V ±2% bandgap reference is hard-wired to COMPIN− (pin 6), and ±3mV internal hysteresis eliminates need for external feedback resistors. Only COMPIN+ (pin 5) requires connection to the signal being monitored - making it a true 3-component solution (device + sensor + pull-up) for threshold detection.

Can the MAX951EPA drive capacitive loads such as ADC inputs or long PCB traces?

Yes, the MAX951EPA op amp is unity-gain stable and characterized to drive ≥1000pF loads without oscillation. Its proprietary output stage maintains linearity and phase margin under heavy capacitive loading - critical for direct connection to SAR ADC sample-and-hold inputs or routed sensor traces on large industrial control boards where stray capacitance exceeds 500pF.

How does the MAX951EPA's reference accuracy compare to discrete alternatives?

The MAX951EPA's internal 1.2V reference achieves ±2% accuracy over –40°C to +85°C without calibration or trimming. Discrete references like REF3012 offer similar initial accuracy but require external decoupling and consume additional board space and supply current. The MAX951EPA integrates reference, comparator, and op amp with matched thermal drift - improving system-level threshold stability beyond what discrete solutions provide.

Is the MAX951EPA pin-compatible with other members of the MAX951–MAX954 family?

Yes, all MAX951–MAX954 variants share identical 8-pin PDIP, SO, μMAX, and CERDIP pinouts. The MAX951EPA is pin-compatible with MAX952EPA, MAX953EPA, and MAX954EPA - enabling drop-in substitution where op amp gain stability (unity vs. ≥10V/V) or reference presence (present in MAX951/MAX952, absent in MAX953/MAX954) aligns with design requirements.