Analog Devices Inc./Maxim Integrated MAX1793EUE25+

Overview

MAX1793EUE25+ from Maxim Integrated is a low-dropout linear regulator (LDO) with pMOS pass transistor, delivering 1A output current at ±1% accuracy with 270mV typical dropout (2.5V preset). It operates from +2.5V to +5.5V input and features integrated reset output (4ms delay), shutdown control, thermal overload protection, and Dual Mode™ operation for fixed or adjustable output. Used in portable instrumentation and handheld computing where low quiescent current and stable voltage regulation are critical.

For engineers reviewing the MAX1793EUE25+ datasheet, MAX1793EUE25+ pinout, MAX1793EUE25+ application, or MAX1793EUE25+ equivalent, key selection criteria include guaranteed 1A load capability, 270mV dropout at 1A, ±1% output accuracy over temperature, 125µA ground current, and TSSOP-EP package thermal performance - all validated for battery-powered systems requiring high reliability and compact footprint.

Technical Context

The MAX1793EUE25+ uses an internal +1.25V reference and error amplifier to regulate output via a p-channel MOSFET pass device, eliminating base-drive current and enabling ultra-low quiescent current (125µA at light load, ≤225µA in dropout). Its Dual Mode™ comparator selects between factory-trimmed 2.5V output (SET = GND) or adjustable mode (1.25V–5.0V) based on SET pin voltage threshold (50–150mV).

It integrates multiple protection functions: short-circuit current limit (1.1–3.3A depending on condition), thermal shutdown at +170°C with ~20°C hysteresis, and open-drain RST output asserting low when VOUT falls 6% below nominal and holding for ≥4ms after recovery. The RST output requires external 100kΩ pullup to OUT or logic rail.

Key Specifications

Pinout & Package

MAX1793EUE25+ is housed in a 16-pin TSSOP-EP (exposed pad) package rated for 1.5W continuous power dissipation at TA = +70°C, with 19mW/°C derating above that temperature. The exposed pad (EP) and GND pin serve as primary thermal paths and must be soldered to a large PCB ground plane (≥1 in² recommended) for optimal thermal performance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and MCP1826T-2502E/DB, the MAX1793EUE25+ uniquely combines 270mV dropout, integrated 4ms RST, Dual Mode™ configurability, and TSSOP-EP thermal efficiency - making it optimal for space-limited, battery-powered systems requiring both precision regulation and system-level supervision.

Availability

MAX1793EUE25+ is available at Aetrix Electronics and suitable for notebook computers, handheld instruments, and cordless telephone base stations requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.

Supply support for MAX1793EUE25+ 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 high-performance analog and mixed-signal semiconductor solutions for power management, sensing, and connectivity applications.

The MAX1793 series was developed specifically for portable electronics demanding ultra-low IQ, high output current, and integrated system supervision - targeting battery-operated devices where runtime, size, and reliability are co-optimized.

FAQ

What is the guaranteed dropout voltage for MAX1793EUE25+ at 1A load?

The MAX1793EUE25+ guarantees a maximum dropout voltage of 450mV at 1A load and TA = +85°C, with typical performance of 270mV. This specification applies when VIN ≥ 3V and SET = GND. The low dropout enables operation down to 2.77V input while sustaining 2.5V output - critical for maximizing Li-ion battery utilization in portable systems.

How does the Dual Mode™ feature work on MAX1793EUE25+?

The Dual Mode™ feature of MAX1793EUE25+ uses the SET pin voltage to automatically select between fixed and adjustable output modes: connecting SET to GND (<50mV) activates the factory-trimmed 2.5V output, while applying >150mV enables adjustable mode (1.25V–5.0V) via external resistors. This eliminates manual configuration and supports flexible design reuse across product variants.

Can MAX1793EUE25+ be used without the exposed pad connected?

No - the exposed pad (EP) of MAX1793EUE25+ must be soldered to the PCB ground plane. It serves as both a thermal conduction path and part of the GND return, contributing significantly to the 1.5W power dissipation rating. Omitting EP connection risks thermal shutdown, reduced output current capability, and long-term reliability degradation due to junction overheating.

What is the function of the RST pin on MAX1793EUE25+ and how should it be interfaced?

The RST pin on MAX1793EUE25+ is an open-drain output that goes low when VOUT falls below 94% of nominal (2.35V) and remains low for ≥4ms after recovery. It requires a 100kΩ pullup resistor to OUT or another logic rail to generate a clean active-high reset signal for microcontrollers. During shutdown, RST is forced low regardless of output voltage.

Does MAX1793EUE25+ support adjustable output voltage, and if so, what is the calculation method?

Yes - MAX1793EUE25+ supports adjustable output from 1.25V to 5.0V using two external resistors connected to the SET pin. The output voltage follows VOUT = 1.25V × [1 + (R1/R2)], where R2 connects SET to GND and R1 connects SET to OUT. Input bias current at SET is <±100nA, allowing high-value resistors (e.g., R2 = 125kΩ) to minimize power loss without compromising accuracy.