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 independent of load or dropout condition. Designed for battery-powered portable electronics requiring stable, quiet voltage regulation.

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, ±1.4% output accuracy over temperature, reverse battery protection, and SOT23-5 regular package compatibility with industry-standard '2982 footprint.

Technical Context

The MAX8878EUK32-T uses an internal P-channel MOSFET pass transistor (1.1Ω typical R_DS(ON)) enabling ultra-low quiescent current (100µA) across all operating conditions-including dropout-and eliminating base-drive losses inherent in PNP-based regulators. Its error amplifier compares a 1.25V bandgap reference against feedback from an internal resistor divider tied to the OUT pin.

It integrates thermal shutdown (155°C trip, 15°C hysteresis), short-circuit protection, and-uniquely versus MAX8877-a logic-controlled auto-discharge function that actively pulls the output to ground via a 300Ω internal resistance during shutdown. The BP pin accepts a 0.01µF ceramic capacitor to form an 80Hz low-pass filter, reducing output noise to 30µVRMS (10Hz–100kHz).

Key Specifications

Pinout & Package

MAX8878EUK32-T is housed in a 5-pin SOT23-5 regular package (JEDEC MO-178AA), with exposed pad not electrically connected. The GND pin serves dual role as electrical return and thermal path; soldering to a large PCB copper area improves thermal performance and power dissipation capability (571mW at +70°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX8878EUK32-T, MAX8877EUK32-T omits auto-discharge but matches all other electrical and mechanical specs, while XC6206P322MR-G trades protection features and precision for lower unit cost - making MAX8878EUK32-T the optimal choice for robust, battery-critical portable designs.

Availability

MAX8878EUK32-T is available at Aetrix Electronics and suitable for cellular handsets, PCMCIA cards, palmtop computers, 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 designed specifically for battery-powered portable electronics demanding ultra-low noise, low dropout, and robust protection features in space-constrained SOT23-5 packages.

FAQ

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

The MAX8878EUK32-T delivers a factory-preset output voltage of 3.15V with ±1.4% accuracy over the full -40°C to +85°C operating range. This value is laser-trimmed during production using an internal resistor divider network - no external components are required or supported for adjustment. The "32" suffix in the part number explicitly denotes 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 integrated auto-discharge function activated when the SHDN pin is driven low. During shutdown, an internal 300Ω switch connects the OUT pin to GND, actively discharging any stored energy in the output capacitor. This prevents floating outputs, avoids backfeeding into downstream circuitry, and eliminates the need for external discharge resistors - a feature absent in the pin-compatible MAX8877EUK32-T.

What are the capacitor requirements for stable operation of MAX8878EUK32-T?

For stable operation, MAX8878EUK32-T requires a minimum 1µF ceramic capacitor (ESR <0.2Ω) on the OUT pin when VOUT ≥2.5V - which applies directly to its 3.15V output. The IN pin needs ≥1µF, and the BP pin requires exactly 0.01µF (low-leakage ceramic). Using capacitors outside these specifications - especially oversized BP caps (>0.1µF) - degrades startup time and shutdown exit delay without improving noise performance.

How does MAX8878EUK32-T protect against reverse battery connection?

MAX8878EUK32-T incorporates dedicated reverse battery protection circuitry that monitors both the IN and SHDN pins. If either falls below GND potential, internal switches disconnect parasitic paths and limit reverse current to ≤1mA - preventing damage to the IC and downstream components. This protection operates independently of enable state and requires no external components, distinguishing it from basic diode-based solutions that waste forward voltage.

What is the thermal performance limit of MAX8878EUK32-T in SOT23-5 regular package?

In the SOT23-5 regular package, MAX8878EUK32-T has a junction-to-board thermal resistance (θ_JB) of 140°C/W. At ambient +70°C, its maximum continuous power dissipation is 571mW - derating by 7.1mW/°C above that temperature. To sustain 150mA output at worst-case dropout (165mV), PCB layout must provide adequate GND copper area; exceeding 150°C junction temperature triggers thermal shutdown at 155°C with 15°C hysteresis.