Analog Devices Inc./Maxim Integrated MAX1793EUE33+

Overview

MAX1793EUE33+ from Maxim Integrated is a low-dropout linear regulator (LDO) with pMOS pass transistor, delivering 1A output current at ±1% accuracy with 210mV dropout at full load. It operates from +2.5V to +5.5V input and provides a factory-preset 3.3V output (or adjustable 1.25V–5.0V via external resistors), used in portable power rails for microcontrollers and RF subsystems in battery-powered handheld instruments.

For engineers reviewing the MAX1793EUE33+ datasheet, MAX1793EUE33+ pinout, MAX1793EUE33+ application, or MAX1793EUE33+ equivalent, key selection criteria include guaranteed 1A load capability under 210mV dropout, 125µA ground current in active mode, 0.1µA shutdown current, 115µVRMS output noise, and integrated reset output with 4ms delay - all critical for space-constrained, low-power embedded systems requiring stable 3.3V supply.

Technical Context

The MAX1793EUE33+ 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 operation. Its Dual Mode™ architecture selects between preset and adjustable output based on SET pin voltage (<50mV for fixed mode).

It integrates thermal-overload protection (trip at +170°C, 20°C hysteresis), short-circuit current limiting (1.1–3.3A depending on condition), and an open-drain RST output that asserts low when VOUT drops below 94% of nominal and holds for ≥4ms after recovery - supporting reliable power-on-reset sequencing.

Key Specifications

Pinout & Package

The MAX1793EUE33+ is housed in a 16-pin TSSOP-EP package (1.5W power rating, 30% smaller than SOT223, 1.1mm height) with exposed thermal pad (EP) soldered to PCB ground plane for enhanced thermal dissipation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A4700RGWR and ADP1741ACPZ-3.3-R7, the MAX1793EUE33+ uniquely combines 1A output, 210mV dropout, ±1% accuracy, integrated RST, and TSSOP-EP thermal performance - making it optimal for compact, battery-powered systems needing both high current and robust power management.

Availability

MAX1793EUE33+ is available at Aetrix Electronics and suitable for notebook computers, cellular phones, and handheld instruments requiring stable component supply with guaranteed long-term availability and RoHS-compliant packaging.

Supply support for MAX1793EUE33+ 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 MAX1793EUE33+ belongs to Maxim's low-IQ LDO family engineered for battery-powered portable equipment - prioritizing ultra-low ground current, small footprint, and integrated system-level features like reset and thermal protection.

FAQ

What is the guaranteed output voltage accuracy of the MAX1793EUE33+ across temperature and load?

The MAX1793EUE33+ guarantees ±1% output voltage accuracy over the full operating temperature range (−40°C to +85°C) and load current (1mA to 1A), with VIN > VOUT + 0.5V. At TA = +85°C and IOUT = 250mA, accuracy remains within ±1% for preset VOUT ≥ 2.5V. This specification is confirmed in the Electrical Characteristics table and applies directly to the MAX1793EUE33+ as a 3.3V variant.

Does the MAX1793EUE33+ support adjustable output voltage, and how is it configured?

Yes, the MAX1793EUE33+ supports adjustable output from 1.25V to 5.0V using an external resistor divider connected to the SET pin. When SET is left unconnected or pulled above 50mV, the device enters adjustable mode; the output follows VOUT = 1.25V × (1 + R1/R2). The MAX1793EUE33+ maintains its 1A rating and 210mV dropout in this mode, as verified in the Detailed Description and Electrical Characteristics sections.

What is the function and timing behavior of the RST pin on the MAX1793EUE33+?

The RST pin on the MAX1793EUE33+ is an open-drain output that goes low when VOUT falls below 94% of nominal (3.102V for 3.3V), and remains low for at least 4ms after VOUT recovers. It serves as a power-on-reset signal and is asserted during shutdown. A 100kΩ pull-up resistor to OUT or another logic rail is required, as specified in the Pin Description and Typical Operating Circuit (Figure 2) for the MAX1793EUE33+.

How does the thermal protection mechanism work in the MAX1793EUE33+?

The MAX1793EUE33+ incorporates thermal-overload protection that disables the pass transistor when junction temperature exceeds +170°C, with ~20°C hysteresis. Once cooled, regulation resumes automatically. This feature prevents permanent damage during sustained overload or poor PCB thermal design. The exposed pad (EP) and GND pin must be soldered to a large ground plane to maintain safe junction temperatures - a requirement explicitly stated in the Applications Information section for the MAX1793EUE33+.

What are the capacitor requirements for stable operation of the MAX1793EUE33+?

The MAX1793EUE33+ requires a 4.7µF input capacitor (CIN) between IN and GND, and a 6.8µF output capacitor (COUT) between OUT and GND. COUT must have ESR ≤ 0.5Ω for stability and optimal transient response; ceramic, low-ESR tantalum, or OS-CON types are recommended. Both capacitors must be placed as close as possible to the MAX1793EUE33+ pins to minimize trace inductance - details confirmed in the Applications Information section.