Analog Devices Inc./Maxim Integrated MAX922ESA+

Overview

The MAX922ESA+ from Maxim Integrated is a dual ultra-low-power voltage comparator with no internal reference and no built-in 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 supply), draws ≤4μA quiescent current over –40°C to +85°C, features rail-to-rail input range (V– to V+ – 1.3V), TTL/CMOS-compatible outputs that both sink and source current, and delivers 40mA continuous output source capability - ideal for battery-powered threshold detection in portable instrumentation and low-power sensor interfaces.

For engineers reviewing the MAX922ESA+ datasheet, MAX922ESA+ pinout, MAX922ESA+ application, or MAX922ESA+ equivalent, key selection considerations include its dual-comparator architecture without integrated reference, absence of HYST/REF pins, compatibility with external hysteresis via positive feedback, and guaranteed operation across industrial temperature range with minimal supply current drift.

Technical Context

The MAX922ESA+ implements two independent micropower comparators with a unique crowbar-free output stage that eliminates switching-induced supply glitches and parasitic feedback. Its input common-mode range extends from V– to (V+ – 1.3V), supporting single-supply operation down to +2.5V and dual-supply operation as low as ±1.25V.

Unlike the MAX921/MAX923, it lacks internal voltage reference and programmable hysteresis circuitry - requiring external reference and resistor-based positive feedback for hysteresis implementation. Output swing is rail-to-rail between V+ and V–, enabling direct interfacing with bipolar or single-supply logic families when V– is grounded.

Key Specifications

Pinout & Package

MAX922ESA+ uses an 8-pin SO (Small Outline) package with exposed pad variant not specified; pin functions are validated per Maxim's official pin configuration diagram for MAX922.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM393DR and TLV3702IDR, the MAX922ESA+ uniquely balances ultra-low 4μA supply current, 40mA output sourcing, and industrial temperature rating - making it optimal for long-life, load-driving dual-threshold applications where reference independence is acceptable.

Availability

MAX922ESA+ is available at Aetrix Electronics and suitable for battery-powered systems, industrial threshold detectors, window comparators, and oscillator circuits requiring stable component supply across extended temperature ranges and consistent low-power performance.

Supply support for MAX922ESA+ 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, interface, and timing applications in industrial, automotive, and communications markets.

The MAX921–MAX924 family was engineered specifically for ultra-low-power comparator applications demanding micropower operation, rail-to-rail inputs, and robust output drive - targeting portable instrumentation, sensor interfaces, and energy-harvesting systems.

FAQ

What is the maximum supply voltage for MAX922ESA+ in single-supply operation?

The MAX922ESA+ supports a maximum single-supply voltage of +11V. This rating applies when V– is connected to ground and V+ is supplied with up to +11V. Operation beyond this voltage risks permanent damage, as confirmed by Absolute Maximum Ratings in the official datasheet. The device also supports dual-supply operation up to ±5.5V, maintaining full functionality across its specified temperature range.

Does MAX922ESA+ include an internal voltage reference?

No, the MAX922ESA+ does not include an internal voltage reference. Unlike the MAX921 and MAX923 variants, the MAX922ESA+ omits the REF and HYST pins and provides no bandgap reference output. Users must supply an external reference voltage to the comparator inputs when implementing precise threshold detection - a design choice enabling greater flexibility and avoiding reference-related noise coupling in sensitive applications.

Can MAX922ESA+ drive an LED directly without a series resistor?

No, MAX922ESA+ must be used with a current-limiting series resistor when driving an LED. Although its output can source up to 40mA continuously, direct connection risks exceeding the LED's absolute maximum forward current and damaging either component. For example, with a red LED (VF ≈ 1.8V) and V+ = 5V, a minimum 80Ω resistor is required to limit current to 40mA. Always verify LED specifications and thermal derating in the final layout.

What is the input voltage range specification for MAX922ESA+?

The MAX922ESA+ input common-mode voltage range is specified as V– to (V+ – 1.3V). This means the inputs can operate down to the negative supply rail (including ground in single-supply mode) and up to 1.3V below the positive supply. For instance, with V+ = 5V and V– = 0V, valid input voltages span 0V to 3.7V. Inputs may tolerate brief excursions beyond these limits (±0.3V) without damage, but guaranteed operation occurs only within the specified range.

How is hysteresis implemented on MAX922ESA+ since it lacks a HYST pin?

Hysteresis on MAX922ESA+ is implemented externally using positive feedback resistors, as detailed in Figure 4 of the datasheet. A resistor network (R1, R2, R3) connects the comparator output back to the noninverting input, creating a voltage-dependent threshold shift. This method requires careful selection of resistor values to balance hysteresis magnitude, input impedance, and accuracy - unlike the simplified HYST-pin approach used in MAX921/MAX923. The technique is fully supported and characterized for MAX922ESA+.