Analog Devices Inc./Maxim Integrated MAX8878EUK32+T

Overview

MAX8878EUK32+T from Maxim Integrated is a low-noise, low-dropout linear regulator with preset 3.15V output, delivering up to 150mA from 2.5V–6.5V input. It features 30µVRMS output noise, 165mV dropout at 150mA, and 100µA operating supply current - designed for battery-powered portable electronics requiring stable, clean voltage rails.

For engineers reviewing the MAX8878EUK32+T datasheet, MAX8878EUK32+T pinout, MAX8878EUK32+T application, or MAX8878EUK32+T equivalent, key selection criteria include its auto-discharge function (exclusive to MAX8878), SOT23-5 regular package compatibility with '2982 footprint, ±1.4% output accuracy, and thermal/reverse-battery protection for robust operation in handheld instruments and telecom devices.

Technical Context

The MAX8878EUK32+T uses an internal P-channel MOSFET pass transistor (1.1Ω typical R_DS(ON)) enabling low dropout and load-independent 100µA quiescent current. Its error amplifier compares a 1.25V bandgap reference against feedback from an internal resistor divider tied to the OUT pin.

It integrates logic-controlled shutdown (10nA I_SHDN), thermal shutdown at +155°C with 15°C hysteresis, short-circuit protection, reverse battery protection (<1mA reverse current), and - uniquely versus MAX8877 - active output discharge via a 300Ω internal resistance when SHDN is asserted.

Key Specifications

Pinout & Package

MAX8878EUK32+T is housed in a RoHS-compliant 5-pin SOT23-5 regular package (JEDEC MO-178AA), with GND serving as both electrical reference and thermal path. The package measures 2.9mm × 1.6mm × 1.1mm and is optimized for high-density PCB layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar low-noise LDO applications.

Compared with MAX8878EUK32+T, MAX8877EUK32+T offers identical regulation performance but omits auto-discharge - making it suitable for simpler systems. The Torex XC6206P322MR-G provides basic LDO functionality at lower cost but sacrifices noise performance, dropout, and advanced protection features essential for precision portable designs.

Availability

MAX8878EUK32+T is available at Aetrix Electronics and suitable for cellular handsets, PCMCIA cards, hand-held instruments, and electronic planners requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX8878EUK32+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 applications.

The MAX8877/MAX8878 product line was engineered specifically for battery-powered portable electronics - emphasizing ultra-low quiescent current, low-noise regulation, and robust fault protection in space-constrained SOT23 packages.

FAQ

What is the exact output voltage of MAX8878EUK32+T and how is it set?

The MAX8878EUK32+T delivers a factory-trimmed 3.15V output with ±1.4% accuracy over temperature and load. This voltage is preset internally using laser-trimmed resistors in the feedback divider - no external components are required or supported. The "32" suffix in the part number directly corresponds to the 3.15V output code per Maxim's expanded ordering table.

Does MAX8878EUK32+T support auto-discharge, and how does it work?

Yes, MAX8878EUK32+T includes an auto-discharge function not present in the MAX8877 series. When the SHDN pin is driven low, an internal 300Ω switch actively discharges the OUT pin to GND. This ensures rapid, controlled ramp-down of the output voltage - critical for preventing back-powering or bus contention in hot-plug systems like PCMCIA cards.

What are the minimum and maximum input voltage requirements for MAX8878EUK32+T?

MAX8878EUK32+T operates from 2.5V to 6.5V input. The minimum usable input is determined by dropout: at 150mA load, VIN must be ≥3.315V (3.15V + 165mV). Below 2.5V, regulation ceases; above 6.5V, absolute maximum ratings are exceeded. For optimal PSRR and noise performance, VIN should exceed VOUT by ≥0.5V under normal operation.

How does the BP pin affect noise and startup time in MAX8878EUK32+T?

The BP pin connects to a 0.01µF ceramic capacitor that forms an 80Hz low-pass filter with an internal 200kΩ resistor, reducing reference noise and lowering total output noise to 30µV_RMS. Increasing BP capacitance reduces noise slightly but increases startup time - values >0.1µF are not recommended due to excessive delay and no meaningful noise benefit per the datasheet's Shutdown Exit Delay graphs.

Is MAX8878EUK32+T pin-compatible with industry-standard regulators?

Yes, MAX8878EUK32+T is pin-compatible with the industry-standard '2982 family of LDOs in the SOT23-5 package. Pin assignments (IN, GND, SHDN, BP, OUT) match exactly, enabling drop-in replacement in existing designs - provided the auto-discharge behavior and 3.15V output are verified compatible with the target application's power sequencing and voltage tolerance requirements.