Analog Devices Inc./Maxim Integrated MAX1726EUK50+TG48

Overview

MAX1726EUK50+TG48 from Maxim Integrated is a fixed-output, ultra-low quiescent current (2µA), low-dropout linear regulator delivering 5.0V at up to 20mA with ±1.5% output voltage accuracy over -40°C to +85°C. It features reverse-battery protection, thermal shutdown, and short-circuit foldback limiting, and is designed for microcontroller power, real-time clock backup, and smoke detector systems powered by two Li+ cells or 9V batteries.

For engineers reviewing the MAX1726EUK50+TG48 datasheet, MAX1726EUK50+TG48 pinout, MAX1726EUK50+TG48 application, or MAX1726EUK50+TG48 equivalent, key selection considerations include its 2µA supply current in dropout, 5-pin SOT23 package, 1.5% output accuracy, 300mV typical dropout at 20mA, and compatibility with 1µF ceramic output capacitance for stable load transients.

Technical Context

The MAX1726EUK50+TG48 uses an internal p-channel MOSFET pass transistor with a 1.245V reference error amplifier, enabling ultra-low IQ without base-drive losses. Its feedback network is fully integrated-no external resistors required-unlike the adjustable MAX1725 variant.

Shutdown is active-low via the SHDN pin (VIH = 0.5V max), reducing supply current to 0.7µA; thermal protection activates at +150°C with 15°C hysteresis, and foldback current limiting caps short-circuit current to ~40mA (typ) while allowing indefinite fault operation.

Key Specifications

Pinout & Package

MAX1726EUK50+TG48 is housed in a RoHS-compliant, lead(Pb)-free 5-pin SOT23 package (outline 21-0057, land pattern 90-0174), measuring 2.9mm × 1.6mm × 1.1mm with gull-wing leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS78050DRVR and MCP1703T-5002E/MB, MAX1726EUK50+TG48 offers the optimal balance of ultra-low 2µA IQ, integrated reverse-battery protection, and proven 5-pin SOT23 compatibility for space-constrained, safety-critical battery systems-without requiring layout changes or external protection components.

Availability

MAX1726EUK50+TG48 is available at Aetrix Electronics and suitable for microcontroller power, real-time clock backup, and smoke detector applications requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for MAX1726EUK50+TG48 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 industrial, medical, communications, and consumer applications.

The MAX1725/MAX1726 product line was engineered specifically for ultra-low-power, battery-critical systems-emphasizing nanoscale IQ, integrated protection, and minimal external component count in miniature packages.

FAQ

What is the guaranteed output current capability of the MAX1726EUK50+TG48?

The MAX1726EUK50+TG48 guarantees 20mA output current across its full operating temperature range (-40°C to +85°C) and input voltage range (2.5V to 12V). While short-circuit foldback limits peak current to ~40mA (typ), continuous operation is rated at 20mA with ≤300mV dropout. Exceeding this may trigger thermal shutdown depending on ambient conditions and PCB copper area.

Does the MAX1726EUK50+TG48 require an external feedback resistor network?

No, the MAX1726EUK50+TG48 does not require external feedback resistors. It integrates a precise internal resistor divider to set the fixed 5.0V output-unlike the adjustable MAX1725 which uses the FB pin. This eliminates component count, layout sensitivity, and long-term drift associated with external resistors, simplifying design and improving reliability.

How does reverse-battery protection work in the MAX1726EUK50+TG48?

The MAX1726EUK50+TG48 incorporates internal circuitry that detects reversed input polarity and disconnects internal parasitic paths, limiting reverse current to <10µA even when VIN is forced below ground. For full protection, Maxim recommends driving the SHDN pin through a 100kΩ resistor-this ensures the IC remains disabled during reverse connection, preventing any forward conduction through the pass device or ESD structures.

What is the minimum output capacitance required for stable operation of the MAX1726EUK50+TG48?

The MAX1726EUK50+TG48 is stable with a minimum 1µF ceramic output capacitor (X5R or X7R dielectric). This value ensures adequate phase margin across -40°C to +85°C and supports fast load transients (e.g., 1mA → 20mA step) with <200mV overshoot/undershoot. Larger values improve PSRR and noise rejection but are not required for basic stability.

Is the MAX1726EUK50+TG48 pin-compatible with other variants in the MAX1726 family?

Yes, all MAX1726 variants-including MAX1726EUK18+T, MAX1726EUK25+T, MAX1726EUK33+T, and MAX1726EUK50+T-share identical 5-pin SOT23 pinout, thermal characteristics, and electrical interface. Only the output voltage differs; no PCB redesign is needed when substituting between fixed-voltage versions, provided the target voltage meets system requirements.