Analog Devices Inc./Maxim Integrated MAX931CPA

Overview

The MAX931CPA from Maxim Integrated is a single micropower comparator with integrated 1.182V ±2% bandgap reference, programmable hysteresis via HYST pin, TTL/CMOS-compatible output sinking and sourcing up to 50mA, and ultra-low 4µA max supply current over 0°C to +70°C. It operates from +2.5V to +11V single supply (or ±1.25V to ±5.5V dual supply) and supports battery-powered threshold detection with rail-to-rail input range down to V− and within 1.3V of V+.

For engineers reviewing the MAX931CPA datasheet, MAX931CPA pinout, MAX931CPA application, or MAX931CPA equivalent, key selection considerations include its 12µs propagation delay at 10mV overdrive, continuous 40mA source capability, absence of crowbar current during switching, internal reference referenced to V− (not GND), and compatibility with low-noise, low-power analog monitoring in portable instrumentation and power management systems.

Technical Context

The MAX931CPA integrates a precision micropower comparator and a 1.182V ±2% bandgap reference on a single die, with the reference output (REF) referenced strictly to V−. Its unique output stage eliminates crowbar current during logic transitions, reducing parasitic supply feedback and improving stability without requiring external bypassing.

Hysteresis is implemented via the HYST pin-accepting voltages from REF − 50mV to REF-and enables simple two-resistor configuration for noise-immune thresholding. Input common-mode range extends from V− to V+ − 1.3V, supporting operation near supply rails in single-supply systems where GND = V−.

Key Specifications

Pinout & Package

MAX931CPA uses an 8-pin plastic DIP package (0°C to +70°C temperature range), with pin 1 = OUT, pin 2 = V−, pin 3 = IN+, pin 4 = IN−, pin 5 = HYST, pin 6 = REF, pin 7 = V+, pin 8 = GND. GND is internally connected to V− for single-supply operation; output swings from V+ to GND.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX921CPA, the MAX931CPA trades 1% reference accuracy for lower supply current and identical pin compatibility; compared with TLV3011IDBVR, it delivers significantly higher output drive and integrated hysteresis control at the cost of higher quiescent current and narrower supply range.

Availability

MAX931CPA is available at Aetrix Electronics and suitable for battery-powered systems, threshold detectors, oscillator circuits, and alarm circuits requiring stable component supply with guaranteed commercial temperature range (0°C to +70°C) and long-term production continuity.

Supply support for MAX931CPA 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 management, sensing, and interface applications, with emphasis on low-power, high-reliability solutions for industrial and portable markets.

The MAX931CPA belongs to the MAX93x micropower comparator family, engineered specifically for ultra-low-power threshold detection and reference-integrated signal conditioning in space-constrained, battery-operated equipment.

FAQ

What is the maximum supply voltage for MAX931CPA in single-supply operation?

The MAX931CPA supports a single-supply voltage range of +2.5V to +11V. When operated with V− tied to GND (standard single-supply configuration), the absolute maximum rating for V+ to GND is +12V, but functional operation is specified up to +11V. Exceeding +11V may degrade reference accuracy or increase supply current beyond datasheet limits.

Can the REF pin of MAX931CPA be used as a standalone voltage reference for other circuits?

Yes, the REF pin of MAX931CPA provides a 1.182V ±2% output referenced to V− and can source up to 15µA or sink up to 8µA. However, it must not be bypassed with capacitors, and loading beyond its specified current limits will shift the reference voltage and increase noise. For dedicated reference use, consider MAX6126 or similar precision references.

Does MAX931CPA support dual-supply operation, and how is it configured?

Yes, MAX931CPA supports dual-supply operation from ±1.25V to ±5.5V. Configure by connecting V+ to positive rail, V− to negative rail, and GND to system ground (not tied to either supply rail). The output swings from V+ to GND, and the reference remains referenced to V−. Input common-mode range extends from V− to V+ − 1.3V.

How is hysteresis implemented on MAX931CPA without external feedback?

MAX931CPA implements hysteresis via the HYST pin: connect R1 between REF and HYST, and R2 between HYST and V−. The voltage at HYST sets hysteresis width - REF − HYST ≈ 50mV max - producing a total hysteresis band up to 100mV. This method avoids phase-margin issues associated with external positive feedback and consumes negligible current.

What is the purpose of the GND pin on MAX931CPA, and how does it differ from V−?

On MAX931CPA, the GND pin (pin 8) is internally connected to V− (pin 2) and serves as the system ground reference for single-supply operation. Unlike V−, which defines the reference node for REF and input common-mode range, GND provides the return path for output current and simplifies PCB routing. In dual-supply use, GND remains at system ground while V− is driven negative.