Analog Devices Inc./Maxim Integrated MAX918ESA+T

Overview

MAX918ESA+T from Maxim Integrated is a nanopower, open-drain comparator with integrated 1.245V ±1.5% reference, guaranteed to operate from +1.8V to +5.5V supply, drawing only 750nA supply current, and featuring Beyond-the-Rails™ input range extending 200mV beyond VEE and VCC. It is designed for ultra-low-power battery monitoring in 2-cell systems.

For engineers reviewing the MAX918ESA+T datasheet, MAX918ESA+T pinout, MAX918ESA+T application, or MAX918ESA+T equivalent, key selection criteria include its open-drain output architecture, internal reference accuracy and temperature coefficient, input common-mode range, propagation delay under capacitive load, and compatibility with mixed-voltage logic interfaces.

Technical Context

The MAX918ESA+T implements a rail-to-rail input stage with 200mV Beyond-the-Rails™ operation and internal 4mV hysteresis to prevent oscillation on slow or noisy inputs. Its open-drain output supports pull-up to voltages up to 6V (VEE + 6V), enabling level translation between disparate supply domains.

It integrates a PNP emitter-follower reference with 95ppm/°C TC, 200kΩ output impedance, and stable operation with any capacitive load. The crowbar-current-free switching architecture minimizes supply current surges during transitions, reducing need for bulk bypassing in battery-sensitive designs.

Key Specifications

Pinout & Package

MAX918ESA+T is housed in an 8-pin SO (Small Outline) package (Package Code S8+2), RoHS-compliant, with 1.27mm lead pitch and standard JEDEC MS-012AC outline.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV3691IDBVR and MAX913ESA+, the MAX918ESA+T uniquely combines ultra-low 750nA current, integrated ±1.5% reference, open-drain output for mixed-voltage interfacing, and Beyond-the-Rails™ input capability - making it the only option among the three that satisfies all four requirements simultaneously in compact 2-cell battery systems.

Availability

MAX918ESA+T is available at Aetrix Electronics and suitable for 2-cell battery monitoring, ultra-low-power telemetry, and medical instrument threshold detection requiring stable component supply and long-term manufacturing continuity.

Supply support for MAX918ESA+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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer markets.

The MAX917–MAX920 family was engineered specifically for nanopower, rail-aware sensing in battery-powered portable equipment - prioritizing sub-µA operation, wide input range, and integrated reference functionality without compromising speed or noise immunity.

FAQ

What is the maximum allowable voltage on the MAX918ESA+T output pin?

The MAX918ESA+T output pin is rated for voltages up to VEE + 6V, as specified in Absolute Maximum Ratings. This allows safe pull-up to 3.3V, 5V, or even higher logic supplies when interfacing with mixed-voltage systems. Exceeding this limit risks permanent damage. The device does not clamp or protect against overvoltage on the output, so external limiting is required if pull-up exceeds 6V above VEE.

Does the MAX918ESA+T require external bypass capacitors?

The MAX918ESA+T does not require external bypass capacitors under typical conditions due to its crowbar-current-free switching architecture and low dynamic supply current variation. However, a 100nF ceramic capacitor placed close to the VCC and VEE pins is recommended when supply impedance is high, traces are long, or electromagnetic interference is present - especially in battery-powered systems where supply filtering impacts overall efficiency.

Can the internal reference of the MAX918ESA+T drive a 10kΩ load?

No - the MAX918ESA+T internal reference has a typical output impedance of 200kΩ and is not designed to drive loads below ~100kΩ. Driving a 10kΩ load will cause significant voltage droop and temperature-dependent error. For such loads, buffer the reference with a low-input-bias-current op amp (e.g., MAX406) or use the reference only for high-impedance divider networks where load current remains below 10nA.

How does the MAX918ESA+T handle overdriven inputs?

The MAX918ESA+T features no phase reversal when inputs are overdriven beyond the supply rails - a critical reliability feature for transient-prone systems. Its input stage includes ESD protection diodes that safely conduct when IN+ or IN− exceeds VEE − 0.3V or VCC + 0.3V, preventing latch-up or damage. This behavior is guaranteed across the full −40°C to +85°C operating range and enables robust operation in noisy or fault-condition environments.

Is the MAX918ESA+T pin-compatible with other devices in the MAX917–MAX920 family?

No - the MAX918ESA+T uses an 8-pin SO package, while the functionally similar MAX918EUK+T uses a 5-pin SOT23 package. Pin assignments differ significantly: the SO version includes two N.C. pins and separates IN− and REF functions onto Pin 3, whereas the SOT23 merges them. Direct PCB replacement is not possible without layout revision. Always verify package footprint and pin mapping using Maxim's official land pattern documents (Outline No. 21-0041).