Analog Devices Inc./Maxim Integrated MAX972CSA

Overview

The MAX972CSA from Maxim Integrated is a single, ultra-low-power, open-drain comparator with no internal voltage reference and no programmable hysteresis, housed in an 8-pin SO package. It operates from a single 2.5V to 11V supply (or ±1.25V to ±5.5V dual supplies), draws ≤4µA supply current over temperature, supports rail-to-rail input common-mode range down to V− and up to V+ − 1.3V, and features an open-drain output sinking to V−. It is used in battery-powered threshold detection where minimal quiescent current and wide supply flexibility are critical.

For engineers reviewing the MAX972CSA datasheet, MAX972CSA pinout, MAX972CSA application, or MAX972CSA equivalent, this page delivers verified technical context, exact pin functions, real-world use cases, and validated alternative options - all grounded in Maxim's official specifications for the MAX972 family and confirmed SO-package implementation.

Technical Context

The MAX972CSA implements a single micropower comparator core with open-drain NMOS output stage sinking to V− (not GND), requiring an external pullup. Its input stage operates with guaranteed common-mode range from V− to (V+ − 1.3V), enabling direct sensing near supply rails. No internal reference or HYST pin is present - unlike MAX971/MAX982 - so external reference and hysteresis must be implemented externally via resistive networks or feedback.

It supports dual-supply operation (±1.25V to ±5.5V) with V− as the negative rail and V+ as the positive rail; in single-supply mode, V− is tied to GND. The output can swing up to 11V above V−, permitting level translation across domains - e.g., converting ±5V inputs to 3.3V logic - without requiring the separate GND pin found on MAX971/MAX974.

Key Specifications

Pinout & Package

Package: 8-pin SO (Small Outline Integrated Circuit), 150-mil width, JEDEC MS-012AC. Pin 1 marked by notch or dot; pin numbering counterclockwise from top-left corner when viewed from top.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX982CSA, MAX972CSA saves ~2µA by omitting the reference, making it superior for multi-year battery life; compared with TLV3701IDBVR, MAX972CSA supports true dual-supply operation and V−-referred sinking - critical for ±5V to 3.3V translation - despite higher quiescent current.

Availability

MAX972CSA is available at Aetrix Electronics and suitable for battery-powered systems, threshold detectors, level translators, and oscillator circuits requiring stable component supply, long-term manufacturability, and guaranteed commercial-temperature performance (0°C to +70°C).

Supply support for MAX972CSA 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 consumer systems.

The MAX97x/MAX98x comparator family targets ultra-low-power, wide-supply monitoring - specifically engineered for battery longevity and rail-flexible sensing in portable and energy-constrained equipment.

FAQ

What is the maximum supply voltage for MAX972CSA in single-supply operation?

The MAX972CSA supports a single-supply voltage range of 2.5V to 11V. When operated with V− tied to GND, the maximum allowable V+ is 11V. Absolute maximum ratings permit V+ up to 12V, but functional operation is only guaranteed up to 11V per the datasheet's Electrical Characteristics tables. Exceeding 11V may compromise parametric performance or reliability.

Does MAX972CSA include an internal voltage reference?

No, the MAX972CSA does not include an internal voltage reference. Unlike MAX971 or MAX982, its ordering table explicitly lists "None" under INTERNAL PRECISION REFERENCE. Users must provide an external reference (e.g., TLV431, REF3012) for threshold-setting applications. This omission contributes to its ultra-low 4µA quiescent current.

Can MAX972CSA operate from dual supplies like ±3V?

Yes, MAX972CSA supports dual-supply operation from ±1.25V to ±5.5V. With V+ = +3V and V− = −3V, the device functions correctly: inputs accept signals from −3V to +1.7V (V+ − 1.3V), and the output sinks to V− (−3V). This configuration enables direct interfacing with bipolar signal sources without level-shifting circuitry.

What is the purpose of the NC pins (pins 5 and 6) on MAX972CSA?

Pins 5 and 6 on the MAX972CSA are no-connect (NC) terminals - physically present but electrically unconnected to the die. They serve no circuit function and must remain unconnected (floating) on the PCB. Routing traces to or placing vias on these pads may introduce parasitic coupling or violate package mechanical integrity; Maxim's pinout diagrams confirm both are NC for all SO-package variants of MAX972.

How does the output stage of MAX972CSA differ from MAX971CSA?

The MAX972CSA output sinks to V−, whereas the MAX971CSA output sinks to GND (a dedicated pin separate from V−). This means MAX972CSA's output voltage swing is referenced to V− - enabling true bipolar-to-single-ended translation (e.g., ±5V input → 3.3V logic) - while MAX971CSA's GND-referenced output is optimized for single-supply level shifting where V− = GND. Their pinouts and internal driver topology are fundamentally distinct.