Analog Devices Inc./Maxim Integrated MAX8881EUT50+T

Overview

MAX8881EUT50+T from Maxim Integrated is a fixed-output, ultra-low-quiescent-current LDO linear regulator delivering 5.0V at up to 200mA with ±1.5% output voltage accuracy, 3.5µA supply current, and integrated reverse-battery protection - designed for long-life battery-powered smoke detectors and real-time clocks.

For engineers reviewing the MAX8881EUT50+T datasheet, MAX8881EUT50+T pinout, MAX8881EUT50+T application, or MAX8881EUT50+T equivalent, key selection criteria include dropout voltage (100mV at 50mA), POK open-drain fault indicator, thermal shutdown at 160°C, and SOT23-6 package compatibility with space-constrained portable systems.

Technical Context

The MAX8881EUT50+T uses an internal 2Ω PMOS pass transistor enabling ultra-low IQ across full load and dropout conditions, unlike PNP-based regulators that increase quiescent current in dropout. Its feedback node (FB) is internally tied to OUT, eliminating external resistors and ensuring factory-trimmed 5.0V output stability over –40°C to +85°C.

It integrates reverse-battery protection limiting IN-to-GND reverse leakage to <1mA, plus foldback current limiting (250mA short-circuit), thermal shutdown with 15°C hysteresis, and a precision 1.25V reference driving an error amplifier that controls the MOSFET driver and POK comparator.

Key Specifications

Pinout & Package

MAX8881EUT50+T is housed in a 6-pin SOT23-6 package (JEDEC MO-178AA, 2.9mm × 2.8mm × 1.3mm), with exposed pad not present - optimized for low-cost, high-volume PCB assembly and thermal performance via standard copper pour.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX8881EUT50+T, TPS7A0550PDBVR offers lower quiescent current but omits critical safety features for battery-reversal and power-fail monitoring, while MCP1700T-5002E/TT trades away protection functions for lower unit cost - making MAX8881EUT50+T the optimal choice for safety-certified, long-life, self-contained battery systems.

Availability

MAX8881EUT50+T is available at Aetrix Electronics and suitable for smoke detectors, battery-powered alarms, remote transmitters, smart battery packs, and real-time clocks requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX8881EUT50+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, automotive, and communications markets.

The MAX8880/MAX8881 product line was engineered specifically for ultra-low-power, reverse-polarity-robust battery regulation in safety-critical portable equipment - emphasizing longevity, reliability, and integrated fault resilience over raw efficiency.

FAQ

What is the maximum input voltage rating for MAX8881EUT50+T?

The MAX8881EUT50+T has an absolute maximum input voltage of +14V relative to GND. Its operational input range is specified from 2.5V to 12V, making it compatible with common battery configurations including dual-cell alkaline (up to ~3.2V), 3S Li-ion (up to 12.6V), and industrial 9–12V supplies. Exceeding 12V during normal operation may degrade long-term reliability despite surviving brief transients.

Does MAX8881EUT50+T require external feedback resistors to set its 5.0V output?

No, MAX8881EUT50+T does not require external feedback resistors. It uses internal precision resistors to fix the output at 5.0V ±1.5%, with the FB pin internally connected to OUT. This eliminates component count, layout sensitivity, and trimming effort - a key differentiator from the adjustable MAX8880 variant and many competing LDOs.

How does the POK output function on MAX8881EUT50+T?

The POK output on MAX8881EUT50+T is an open-drain signal that pulls low when the regulated 5.0V output falls below 4.5V (90% of nominal) and remains low during shutdown. It features 1.5% hysteresis to prevent chatter near the trip point. To use it, connect a pull-up resistor (e.g., 100kΩ) to VOUT or another logic rail; no external capacitor is needed unless delayed reset timing is required.

Can MAX8881EUT50+T survive reverse battery connection?

Yes, MAX8881EUT50+T includes integrated reverse-battery protection that limits reverse current into the IN pin to less than 1mA when VIN is forced below ground (down to –14V). This prevents damage to the IC and downstream circuitry. For full SHDN pin protection, a 100kΩ series resistor is recommended - a feature confirmed in the device's functional diagram and Absolute Maximum Ratings table.

What thermal protection mechanism does MAX8881EUT50+T implement?

MAX8881EUT50+T incorporates thermal shutdown that activates at +160°C junction temperature, turning off the PMOS pass transistor. After activation, it remains off until the die cools by 15°C (to ~145°C), then resumes regulation - creating a pulsed output under sustained overload. This auto-recovery behavior avoids permanent latch-off and enables fault-tolerant operation in thermally constrained enclosures without external thermal management.