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 at 12V input, and integrated reverse-battery protection - designed for long-life battery-powered smoke detectors and smart battery packs.

For engineers reviewing the MAX8881EUT50-T datasheet, MAX8881EUT50-T pinout, MAX8881EUT50-T application, or MAX8881EUT50-T equivalent, key selection criteria include dropout voltage (100–200mV at 50mA), POK open-drain fault indicator behavior, SOT23-6 package thermal limits (696mW at +70°C), and compatibility with 1µF input / 4.7µF output ceramic capacitors.

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 current to <1mA, thermal shutdown at +160°C (15°C hysteresis), and foldback current limiting (250mA short-circuit). The open-drain POK output asserts low when VOUT drops >10% below regulation or during shutdown.

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 - suitable for compact, cost-sensitive PCB layouts requiring minimal board area and standard reflow profiles.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS78250DRVR and MCP1700T-5002E/TT, the MAX8881EUT50-T uniquely combines reverse-battery protection, POK flag, and 3.5µA IQ in a standard SOT23-6 - making it optimal for safety-critical, long-life battery systems where component count and fault resilience matter.

Availability

MAX8881EUT50-T is available at Aetrix Electronics and suitable for smoke detectors, battery-powered alarms, remote transmitters, and smart battery packs requiring stable component supply, long-term 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 consumer applications.

The MAX8880/MAX8881 product line was engineered specifically for ultra-low-power, reverse-polarity-resilient battery regulation - targeting applications where decades-long shelf life and robustness against user-induced faults are non-negotiable.

FAQ

What is the maximum continuous output current of the MAX8881EUT50-T?

The MAX8881EUT50-T delivers up to 200mA continuously under specified thermal conditions (TA ≤ +70°C, 696mW max power dissipation in SOT23-6). At higher ambient temperatures or with limited PCB copper area, derating applies - e.g., at +85°C, max continuous current drops to ~140mA based on thermal resistance and junction temperature limits. The device also features foldback current limiting (250mA at VIN = 5V) for short-circuit survival.

Does the MAX8881EUT50-T require external feedback resistors to set its output voltage?

No, the MAX8881EUT50-T does not require external feedback resistors. It is a factory-preset fixed-output regulator with internal precision resistors connecting FB to OUT, delivering 5.0V ±1.5% over –40°C to +85°C. Unlike the adjustable MAX8880, the MAX8881EUT50-T's FB pin is internally tied to OUT - simplifying design, reducing BOM count, and improving long-term voltage stability.

How does reverse-battery protection work in the MAX8881EUT50-T?

The MAX8881EUT50-T incorporates an internal circuit that monitors IN polarity and disconnects internal circuitry and parasitic paths when VIN falls below GND. This limits reverse current to <1mA at –12V, preventing damage or battery drain during accidental backward insertion. For full SHDN pin protection, a 100kΩ series resistor is recommended - but the core IN-to-GND reverse protection is fully integrated and requires no external components.

What capacitor values are required for stable operation of the MAX8881EUT50-T?

The MAX8881EUT50-T is stable with a minimum 1µF X5R/X7R ceramic input capacitor and a 4.7µF output capacitor (ESR < 0.5Ω) for loads up to 200mA. For loads ≤40mA, a 1µF output capacitor suffices. Larger output capacitance (e.g., 10µF) improves transient response and PSRR above 10kHz. Avoid Z5U/Y5V dielectrics due to ESR drift at temperature extremes - X7R or X5R ensures stability across –40°C to +85°C.

Can the POK output of the MAX8881EUT50-T drive a microcontroller reset pin directly?

Yes, the open-drain POK output of the MAX8881EUT50-T can directly interface with most MCU reset pins when pulled up to the same 5V rail (or VCC) via a 10–100kΩ resistor. POK sinks current when VOUT drops below 90% of nominal (4.5V) or during shutdown, asserting a logic-low reset signal. No level-shifting or buffering is needed - but ensure the MCU's reset pin leakage current is <100nA to avoid false releases caused by POK off-state leakage.