Analog Devices Inc./Maxim Integrated MAX972CUA+T

Overview

The MAX972CUA+T from Maxim Integrated is a single-channel, ultra-low-power, open-drain comparator with no internal voltage reference and no programmable hysteresis, housed in an 8-pin µMAX package. It operates from a single 2.5V to 11V supply (or ±1.25V to ±5.5V dual supplies), draws ≤4µA quiescent current over temperature, supports rail-to-rail input common-mode range (V− to V+ − 1.3V), and features open-drain output capable of sinking up to 50mA - ideal for battery-powered threshold detection in portable instrumentation.

For engineers reviewing the MAX972CUA+T datasheet, MAX972CUA+T pinout, MAX972CUA+T application, or MAX972CUA+T equivalent, key selection considerations include its lack of internal reference (requiring external reference or resistor-divider thresholds), absence of HYST pin (necessitating external positive-feedback hysteresis), 12µs propagation delay at 10mV overdrive, separate GND pin for output stage, and compatibility with 3V/5V single-supply systems where minimal power budget is critical.

Technical Context

The MAX972CUA+T implements a micropower comparator core without integrated bandgap reference or hysteresis control circuitry - distinguishing it from MAX971/MAX982 variants. Its input stage accepts voltages from V− to (V+ − 1.3V), enabling operation near supply rails, and its open-drain output connects to a dedicated GND pin (Pin 1), allowing bipolar-to-single-ended level translation even when V+ is unpowered.

Unlike MAX971/MAX982, the MAX972CUA+T lacks REF and HYST pins; hysteresis must be implemented externally via feedback resistors. Its output sink capability is specified down to V− + 0.4V at 1.8mA load, and propagation delay increases at low supply voltages - e.g., rising from 12µs (5V) to >100µs (2.5V) under 10mV overdrive with 100pF load and 1MΩ pullup.

Key Specifications

Pinout & Package

Package: 8-pin µMAX (3mm × 3mm, 0.5mm pitch), thermally enhanced with exposed pad. Pin 1 = OUTA (open-drain output), Pin 2 = V− (negative supply), Pin 3 = INA+ (noninverting input), Pin 4 = INA− (inverting input), Pin 5 = NC, Pin 6 = NC, Pin 7 = V+ (positive supply), Pin 8 = GND (output-stage ground).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX972CUA+T, MAX971CUA+T adds integrated reference and hysteresis control at modest current cost, while TLV3701IDBVR trades output flexibility and voltage range for smaller footprint and lower quiescent current - making MAX972CUA+T optimal for robust, reference-free level translation in 3V/5V industrial systems.

Availability

The MAX972CUA+T is available at Aetrix Electronics and suitable for battery-powered systems, threshold detectors, and level translators requiring stable component supply, long-term obsolescence management, and guaranteed traceability for medical and industrial end equipment.

Supply support for MAX972CUA+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 connectivity applications, with emphasis on low-power innovation and rugged performance.

The MAX97x/MAX98x comparator family targets ultra-low-power, open-drain sensing in portable and energy-harvesting systems - delivering micropower operation without sacrificing input range, output drive, or thermal stability.

FAQ

Does the MAX972CUA+T include an internal voltage reference?

No, the MAX972CUA+T does not include an internal voltage reference. Unlike MAX971CUA+T or MAX982CUA+T, it lacks both REF and HYST pins. Thresholds must be established externally using resistor dividers or precision references. This design reduces quiescent current and die area, making MAX972CUA+T optimal for applications where reference independence and minimal power are prioritized over integration.

What is the function of Pin 8 (GND) on the MAX972CUA+T?

Pin 8 is the dedicated output-stage ground for the open-drain MOSFET. It is electrically separate from the analog input ground (V−) and must be connected to the system ground plane that handles output switching current. This isolation prevents ground bounce from coupling into the comparator's sensitive input stage - a critical feature for noise-immune threshold detection in MAX972CUA+T-based designs.

Can the MAX972CUA+T operate from a 2.5V single supply?

Yes, the MAX972CUA+T is fully specified for operation from a 2.5V to 11V single supply. At 2.5V, input common-mode range extends from V− (0V) to 1.2V, and propagation delay increases to approximately 100µs (10mV overdrive, 100pF load). The output remains functional, sinking current to Pin 8 (GND), though sink strength decreases - verify VOL ≤ 0.4V at required load current per the 2.5V electrical characteristics table.

How is hysteresis implemented on the MAX972CUA+T?

Hysteresis on the MAX972CUA+T requires external positive feedback, as the device has no HYST pin. A resistor network connects the open-drain output (Pin 1) back to the inverting input (Pin 4) through a pullup to V+. This creates a Schmitt-trigger response: output low raises the effective threshold, and output high lowers it. Component values must balance hysteresis width against input bias current error - typical designs use ≥1MΩ feedback resistors to minimize loading on the 0.01nA input.

Is the MAX972CUA+T pin-compatible with other MAX97x comparators in µMAX packages?

No, the MAX972CUA+T is not pin-compatible with MAX971CUA+T, MAX973CUA+T, or MAX982CUA+T in the 8-pin µMAX package. While all share the same physical outline, pin functions differ significantly: MAX972CUA+T uses Pins 5 and 6 as NC, whereas MAX971CUA+T assigns them to REF and HYST. Interchanging them will result in non-functional circuits or potential damage due to incorrect reference or hysteresis connections.