Analog Devices Inc./Maxim Integrated MAX8875EUK29

Overview

The MAX8875EUK29 from Maxim Integrated is a 2.9V fixed-output, 150mA low-dropout linear regulator with P-channel MOSFET pass element, 85µA no-load quiescent current, and active-low open-drain Power-OK (POK) output - designed for battery-powered portable electronics including cellular phones, modems, and PCMCIA cards.

For engineers reviewing the MAX8875EUK29 datasheet, MAX8875EUK29 pinout, MAX8875EUK29 application, or MAX8875EUK29 equivalent, key selection criteria include dropout voltage (110mV @100mA), ±1% output accuracy, reverse-battery protection, thermal shutdown at +170°C, and compatibility with 1µF ceramic output capacitors.

Technical Context

The MAX8875EUK29 employs an internal 1.25V bandgap reference and error amplifier to regulate its factory-set 2.9V output via feedback through an integrated resistor divider. Its P-channel MOSFET pass transistor (typ. R_DS(ON) = 1.1Ω) eliminates base-drive current, enabling load-independent 85µA quiescent supply current.

Power-OK monitoring is implemented with an open-drain N-channel MOSFET that asserts low when V_OUT falls >1% below nominal due to dropout, overcurrent, or thermal shutdown. The POK function remains inactive during SHDN assertion and operates down to V_IN ≤1V for power-on-reset generation.

Key Specifications

Pinout & Package

MAX8875EUK29 is housed in a space-constrained 5-pin SOT23-5 package (2.9mm × 1.6mm × 1.1mm), with GND serving dual roles as electrical reference and thermal path - requiring soldering to a PCB ground plane or large copper pad for reliable power dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX8875EUK29, MAX8885EUK29-T trades lower quiescent current for higher ESR tolerance, while MCP1702T-2902E/MB offers greater current headroom at the cost of missing critical battery-protection features and system-monitoring capability.

Availability

MAX8875EUK29 is available at Aetrix Electronics and suitable for cellular telephones, PCMCIA cards, modems, hand-held instruments, and cordless telephones requiring stable component supply, long-term lifecycle support, and guaranteed parametric compliance.

Supply support for MAX8875EUK29 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 fabless semiconductor company specializing in high-performance analog, mixed-signal, and power-management ICs for industrial, communications, and consumer applications.

The MAX8875 series was engineered specifically for ultra-low-power, battery-critical portable systems - prioritizing minimal quiescent current, robust fault protection, and seamless integration with ceramic capacitors in space-constrained SOT23 footprints.

FAQ

What is the exact output voltage tolerance of the MAX8875EUK29?

The MAX8875EUK29 delivers a factory-trimmed 2.9V output with ±1% initial accuracy over temperature (–40°C to +85°C) and line/load conditions. This specification is 100% production tested at +25°C and guaranteed across the full operating range via Statistical Quality Control correlation - ensuring consistent performance in battery-powered applications where voltage margin is critical for logic compatibility.

Does the MAX8875EUK29 require an external pull-up resistor on the POK pin?

Yes, the MAX8875EUK29 POK pin is an open-drain N-channel MOSFET output and requires an external pull-up resistor to generate a valid logic-high level. A 100kΩ resistor connected to the OUT pin is recommended per the datasheet; larger values reduce current consumption but increase rise time, while smaller values improve speed at the expense of higher static current. Leaving POK unconnected disables the Power-OK function.

Can the MAX8875EUK29 operate with input voltages below 2.5V?

No - the MAX8875EUK29 has a specified minimum input voltage of +2.5V per Absolute Maximum Ratings and Electrical Characteristics tables. Operation below this threshold risks undefined behavior, including failure to regulate, POK malfunction, or inability to exit shutdown. For sub-2.5V battery inputs, alternative regulators such as the MAX8860 (1.8V min) must be evaluated.

What thermal derating applies to the MAX8875EUK29 in a standard SOT23-5 layout?

In a typical 5-pin SOT23-5 footprint with GND soldered to a 100mm² internal ground plane, the MAX8875EUK29 exhibits θ_JA ≈ 140°C/W. At ambient +70°C, its continuous power dissipation must be limited to 571mW (derated 7.1mW/°C above +70°C). For example, at 150mA load and 3.01V dropout (VIN = 5.9V), power dissipation is 0.89W - exceeding safe limits unless enhanced thermal design (e.g., external copper pour, thermal vias) is implemented.

Is the MAX8875EUK29 compatible with X7R ceramic output capacitors?

Yes - the MAX8875EUK29 is explicitly characterized and guaranteed stable with 1µF X7R or X5R ceramic capacitors (ESR <0.2Ω) for output voltages ≥2.5V. These dielectrics maintain capacitance and ESR consistency across –40°C to +85°C, eliminating the need for derating or oversized capacitors. Z5U/Y5V types are not recommended due to excessive parameter drift at temperature extremes.