Analog Devices Inc./Maxim Integrated MAX971CSA+T

Overview

MAX971CSA+T from Maxim Integrated is a single, ultra-low-power, open-drain comparator with integrated 1.182V ±1% precision voltage reference and programmable hysteresis via HYST pin. It operates from 2.5V to 11V single supply (or ±1.25V to ±5.5V dual), draws ≤4µA quiescent current over temperature, supports rail-to-rail input down to V− and within 1.3V of V+, and features separate GND pin for output stage-enabling bipolar-to-single-ended level translation in battery-powered threshold detectors.

For engineers reviewing the MAX971CSA+T datasheet, MAX971CSA+T pinout, MAX971CSA+T application, or MAX971CSA+T equivalent, key selection criteria include its 4µA max supply current at +70°C, 12µs propagation delay (10mV overdrive), ±10mV input offset, open-drain output with 11V output range referenced to GND, and internal reference accuracy critical for low-power window detection and power-good monitoring.

Technical Context

The MAX971CSA+T integrates a bandgap voltage reference (1.182V ±1% over 0°C to +70°C) and a single comparator with hysteresis control via dedicated HYST pin-allowing simple resistor-based hysteresis programming without external feedback. Its open-drain output sinks to GND (not V−), enabling direct interfacing with higher-voltage logic or pull-up domains independent of the comparator's negative supply.

Input common-mode range extends from V− to (V+ − 1.3V); inputs tolerate ±0.3V beyond rails. Propagation delay is specified at 12µs (high-to-low, 10mV overdrive, 100pF load, 1MΩ pullup), with low-to-high response governed by external RC time constant-making timing behavior design-controllable rather than fixed.

Key Specifications

Pinout & Package

MAX971CSA+T is housed in an 8-pin SO (Small Outline) package with gull-wing leads, JEDEC MS-012AC compliant, 150-mil body width, 1.75mm max height.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar comparator applications.

Compared with MAX971CSA+T, MAX921CSA+ offers push-pull output but consumes more current and lacks open-drain flexibility, while TLV3701IDBVR achieves lower quiescent current but forfeits integrated reference and high-voltage capability-making MAX971CSA+T optimal for reference-dependent, level-shifting, or wide-supply applications.

Availability

MAX971CSA+T is available at Aetrix Electronics and suitable for battery-powered systems, threshold detectors, and level translators requiring stable component supply, long-term lifecycle support, and guaranteed commercial-temperature performance (0°C to +70°C).

Supply support for MAX971CSA+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 and mixed-signal ICs for power, sensing, and interface applications in industrial, medical, and communications systems.

The MAX971CSA+T belongs to Maxim's micropower comparator family, engineered specifically for ultra-low-power sensing, battery monitoring, and rail-detection tasks where supply current, reference accuracy, and flexible output configuration are critical.

FAQ

What is the maximum supply voltage for MAX971CSA+T?

The MAX971CSA+T supports a total supply voltage (V+ − V−) up to 11V in single-supply mode (V− = GND) or ±5.5V in dual-supply mode. Absolute maximum ratings allow V+ to V− up to +12V, but operation above 11V is not characterized or guaranteed. For reliable performance, maintain V+ − V− ≤ 11V per the Electrical Characteristics table.

Does MAX971CSA+T require an external reference?

No, MAX971CSA+T includes an internal 1.182V ±1% precision bandgap reference accessible at the REF pin. This reference is referenced to V−, not GND, and can source up to 25µA or sink up to 15µA. External reference is unnecessary unless tighter accuracy or different voltage is required.

Can MAX971CSA+T operate from a 3V single supply?

Yes, MAX971CSA+T is fully specified for 3V single-supply operation (V+ = 3V, V− = GND). Supply current remains ≤4µA, input common-mode range covers 0V to 1.7V, and propagation delay is 12µs (10mV overdrive). The internal reference maintains ±1% accuracy across 0°C to +70°C at 3V.

What is the purpose of the HYST pin on MAX971CSA+T?

The HYST pin on MAX971CSA+T enables simple, resistor-programmable hysteresis: connecting R1 between REF and HYST and R2 between HYST and V− sets a hysteresis band up to 100mV. This prevents output chatter near threshold crossings-critical for noisy sensor inputs or slow-rising supply rails-without external op-amps or feedback networks.

Is MAX971CSA+T pin-compatible with other MAX97x/MAX98x comparators?

No, MAX971CSA+T is not pin-compatible with MAX972, MAX973, or MAX98x variants. While all share the 8-pin SO package footprint, pin functions differ significantly-for example, MAX972 lacks REF and HYST pins, and MAX973 has dual comparators. Always verify pin mapping using the "Pin Description" table in the MAX971–MAX984 datasheet before board reuse.