Analog Devices Inc./Maxim Integrated MAX8875EUK50

Overview

The MAX8875EUK50 from Maxim Integrated is a 5.0V fixed-output, 150mA low-dropout linear regulator with P-channel MOSFET pass device, 85µA no-load quiescent current, and active-low open-drain Power-OK (POK) output - designed for battery-powered portable electronics requiring stable voltage under light-to-moderate load and tight input voltage headroom.

For engineers reviewing the MAX8875EUK50 datasheet, MAX8875EUK50 pinout, MAX8875EUK50 application, or MAX8875EUK50 equivalent, key selection criteria include dropout voltage at 100mA (110mV), ±1% output accuracy over temperature, reverse-battery protection, thermal shutdown at +170°C, and compatibility with 1µF ceramic output capacitors.

Technical Context

The MAX8875EUK50 employs an internal 1.25V bandgap reference and error amplifier to regulate output via feedback through a factory-trimmed resistor divider. Its P-channel MOSFET pass transistor (typical R_DS(ON) ≈ 1.1Ω) eliminates base-drive current, enabling load-independent 85µA supply current.

Power-OK monitoring is implemented with an open-drain N-channel comparator referenced to V_OUT; POK asserts low when V_OUT falls >1% below nominal (e.g., <4.95V for 5.0V version) during dropout, overload, or thermal shutdown. Shutdown logic disables regulation while holding IQ ≤1µA.

Key Specifications

Pinout & Package

MAX8875EUK50 is housed in a space-constrained 5-pin SOT23-5 package (2.9mm × 1.6mm × 1.1mm), with GND serving dual electrical and thermal functions - requires soldering to a large copper pad or ground plane for reliable power dissipation up to 571mW at +70°C ambient.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-dropout regulator applications.

Compared with MAX8875EUK50, MAX8885EUK50-T offers identical pinout and function but trades lower noise for higher-ESR capacitor flexibility, while MCP1700T-5002E/TT reduces cost and quiescent current at the expense of supervision features and fault resilience.

Availability

MAX8875EUK50 is available at Aetrix Electronics and suitable for PCS telephones, cellular telephones, and modems requiring stable component supply, long-term lifecycle support, and guaranteed parametric compliance across industrial temperature ranges.

Supply support for MAX8875EUK50 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, mixed-signal, and power-management ICs for demanding industrial, automotive, and communications applications.

The MAX8875 series was developed specifically for ultra-low-quiescent-current, high-accuracy regulation in space-constrained, battery-powered portable equipment - emphasizing dropout performance, supervision integrity, and robustness under real-world fault conditions.

FAQ

What is the minimum input voltage required for the MAX8875EUK50 to maintain 5.0V output at 100mA?

The MAX8875EUK50 requires a minimum input voltage of 5.11V to sustain 5.0V output at 100mA load, based on its guaranteed 110mV dropout voltage. This allows operation down to the final usable voltage of a single-cell Li-ion battery (~5.1V), extending effective discharge time before system brownout. The MAX8875EUK50 achieves this with its P-channel MOSFET pass element and low R_DS(ON).

Does the MAX8875EUK50 require an external pull-up resistor on the POK pin?

Yes, the MAX8875EUK50 POK pin is an open-drain N-channel output and requires an external pull-up resistor to generate a valid logic-high level. A 100kΩ resistor pulled to the OUT pin is recommended per the datasheet to minimize current draw while ensuring clean signal transitions. Leaving POK unconnected renders the power-OK function inoperative, and the MAX8875EUK50 will not provide fault indication.

Can the MAX8875EUK50 be used with a 10µF output capacitor instead of the specified 1µF?

Yes, the MAX8875EUK50 remains stable with a 10µF ceramic output capacitor and benefits from improved PSRR, reduced output noise, and enhanced load-transient response. The datasheet explicitly recommends larger capacitors for noise-sensitive applications. However, ensure the capacitor's ESR stays below 0.2Ω - X7R or X5R dielectrics are preferred over Z5U/Y5V to maintain stability across the full -40°C to +85°C range of the MAX8875EUK50.

How does reverse-battery protection work in the MAX8875EUK50?

The MAX8875EUK50 incorporates dedicated circuitry that monitors polarity on both IN and SHDN pins; if either falls below GND, internal switches disconnect parasitic paths and limit reverse current to ≤1mA. This prevents destructive current flow and permanent damage during accidental battery reversal - a critical safeguard in consumer handsets where users may insert batteries incorrectly. No external components are needed to enable this protection in the MAX8875EUK50.

Is the MAX8875EUK50 compatible with lead-free reflow soldering processes?

Yes, the MAX8875EUK50 in SOT23-5 package is rated for standard lead-free reflow profiles, including peak temperatures up to +260°C for 10 seconds, as confirmed by Maxim's package documentation. Its Pb-free terminal finish and JEDEC-compliant construction ensure reliable solder joint formation without delamination or voiding. Thermal design must still account for the device's θ_JA of 140°C/W and maximum junction temperature of +150°C during operation.