Analog Devices Inc./Maxim Integrated MAX951EUA+T

Overview

MAX951EUA+T from Maxim Integrated is a micropower, single-supply analog IC integrating a unity-gain-stable operational amplifier, a comparator with internal 1.2V ±2% bandgap reference, and rail-to-rail output stages in an 8-pin μMAX package. It operates from 2.7V to 7V, draws 7μA typical supply current, and supports input common-mode range from VSS to VDD − 1.6V - enabling direct sensor interfacing in battery-powered smoke detectors and infrared receivers.

For engineers reviewing the MAX951EUA+T datasheet, MAX951EUA+T pinout, MAX951EUA+T application, or MAX951EUA+T equivalent, this device is selected for ultra-low-power signal conditioning where simultaneous amplification, threshold detection, and stable reference generation are required in space-constrained, long-life portable systems.

Technical Context

The MAX951EUA+T implements a monolithic CMOS architecture combining three functional blocks: a unity-gain-compensated op amp (20kHz GBW, 12.5V/ms slew rate), a comparator with ±3mV internal hysteresis and rail-to-rail CMOS output capable of sourcing up to 40mA, and a buffered 1.2V bandgap reference referenced to VSS with ±2% accuracy over −40°C to +85°C.

Its input stage supports ground-sensing operation (CMVR includes VSS), and both op amp and comparator outputs swing rail-to-rail - eliminating level-shifting circuitry in single-supply designs. The internal reference is not bypassed and is stable only with capacitive loads <100pF, while the op amp drives ≥1000pF loads without oscillation.

Key Specifications

Pinout & Package

MAX951EUA+T is housed in an 8-pin μMAX package (2.1mm × 2.1mm, 0.5mm pitch), RoHS-compliant, with exposed pad for thermal enhancement. Pin numbering follows standard SO/μMAX top-view convention.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX952EUA+T, the MAX951EUA+T offers lower bandwidth but guaranteed unity-gain stability for high-impedance sensor buffering; compared with TLV2304IDR-based solutions, it delivers 3× smaller footprint and eliminates inter-device timing skew and layout complexity - critical for cost-sensitive, space-constrained alarms and detectors.

Availability

MAX951EUA+T is available at Aetrix Electronics and suitable for battery-powered instruments, safety sensors, and infrared receivers requiring stable component supply with extended lifecycle support.

Supply support for MAX951EUA+T 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, mixed-signal, and power management ICs for industrial, medical, and consumer applications.

The MAX951–MAX954 family was developed to consolidate op amp, comparator, and reference functions into one ultra-low-power, single-supply IC for portable and safety-critical sensing systems - targeting smoke detectors, IR remotes, and handheld instrumentation.

FAQ

What is the operating temperature range for MAX951EUA+T?

The MAX951EUA+T is specified for operation from −40°C to +85°C (industrial grade), matching the E-grade temperature qualification per its ordering code "EUA". This range covers demanding environments such as enclosed smoke detectors and outdoor IR receivers, with full electrical performance guaranteed across the span - including reference accuracy, input offset, and propagation delay.

Can the internal 1.2V reference of MAX951EUA+T be used to bias external circuitry?

Yes, the REF pin (pin 6) of MAX951EUA+T can source or sink up to ±20μA while maintaining ±2% accuracy. It is intended for biasing external comparators, ADC references, or op amp feedback networks - but must not be bypassed with capacitors, as this causes instability. Load regulation is 0.1% for ±20μA, making it suitable for low-current biasing in sensor signal chains.

Does MAX951EUA+T require external compensation for op amp stability?

No, the op amp in MAX951EUA+T is internally compensated for unity-gain stability and remains stable driving ≥1000pF capacitive loads without external components. This eliminates the need for feedback compensation networks in photodiode transimpedance or high-Z sensor buffer configurations - a key advantage over decompensated alternatives like MAX952EUA+T.

How does the comparator hysteresis in MAX951EUA+T improve noise immunity?

The MAX951EUA+T comparator includes fixed ±3mV internal hysteresis, creating a 6mV input window that prevents output oscillation during slow or noisy transitions - e.g., ambient light ramping in IR receivers or gradual voltage rise in smoke chamber plates. This eliminates external hysteresis resistors and associated supply current penalties while ensuring clean, chatter-free digital output.

Is MAX951EUA+T pin-compatible with other variants in the MAX951–MAX954 family?

Yes, all MAX951–MAX954 variants - including MAX951EUA+T, MAX952EUA+T, MAX953EUA+T, and MAX954EUA+T - share identical 8-pin μMAX pinouts and footprints. Functional differences (e.g., presence/absence of internal reference, unity-gain vs. decompensated op amp) do not affect physical layout, enabling drop-in replacement during design iteration or qualification.