Analog Devices Inc./Maxim Integrated MAX8557ETE+T

Overview

MAX8557ETE+T from Maxim Integrated is a 4A ultra-low-input-voltage LDO regulator with p-channel MOSFET pass device, operating from 1.425V to 3.6V input and delivering adjustable output from 0.5V to VIN − 0.2V; features 100mV typical dropout at 4A, ±1% output accuracy over load/line/temperature, and integrated 140ms power-on reset (POR) output; used in point-of-load supplies for optical modules and base station RF subsystems.

For engineers reviewing the MAX8557ETE+T datasheet, MAX8557ETE+T pinout, MAX8557ETE+T application, or MAX8557ETE+T equivalent, this page delivers verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative parts with functional distinctions, and supply-chain support details specific to high-current low-voltage regulation in telecom and server infrastructure.

Technical Context

The MAX8557ETE+T uses an internal 25mΩ p-channel MOSFET pass transistor enabling stable operation down to 1.425V input without charge pump or external bias supply; its feedback loop regulates FB to 0.5V with ±5mV threshold accuracy across −40°C to +85°C, supporting precise output setting via resistor divider.

It integrates dedicated POR logic that transitions to high-impedance state 140ms after VOUT reaches 90% of nominal value, with fault recovery pulling POR low on thermal shutdown or EN deactivation; short-circuit protection employs foldback current limiting (3A max during fault) and thermal shutdown at +160°C junction temperature, with automatic restart at +115°C.

Key Specifications

Pinout & Package

MAX8557ETE+T is housed in a 16-pin TQFN package (5mm × 5mm, exposed paddle), optimized for thermal performance in high-current applications; the EP pad must be soldered to a solid GND plane with ≥9 thermal vias for reliable 4A operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TPS7A84A01RTJT and NCP1117ST50T3G, the MAX8557ETE+T uniquely combines 4A delivery from 1.425V input, adjustable output down to 0.5V, and integrated 140ms POR - making it the sole option for thermally constrained, low-voltage, high-current, and sequenced-power applications in optical and wireless infrastructure.

Availability

MAX8557ETE+T is available at Aetrix Electronics and suitable for optical transceivers, 5G base station RF front-ends, and enterprise SSD controller power requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for MAX8557ETE+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, designs precision analog, mixed-signal, and power management ICs for demanding industrial, communications, and computing applications.

The MAX8557ETE+T belongs to Maxim's ultra-low-input-voltage LDO family, engineered specifically for high-current point-of-load regulation in space-constrained telecom and datacenter systems where input rails fall below 1.5V.

FAQ

What is the minimum input voltage required for stable operation of the MAX8557ETE+T?

The MAX8557ETE+T operates stably down to 1.425V input voltage, with guaranteed 4A output and ±1% accuracy across −40°C to +85°C. Below this threshold, undervoltage lockout activates at 1.35V (typ) rising, preventing erratic regulation. This enables direct use with single-cell Li-ion batteries or low-voltage intermediate distribution buses where traditional LDOs fail.

How does the POR output of the MAX8557ETE+T function in system power sequencing?

The POR output of the MAX8557ETE+T is an open-drain signal that remains low until the output reaches 90% of its nominal voltage, then transitions to high-impedance after a precise 140ms (typ) delay. It pulls low again instantly upon thermal fault or EN deactivation. This behavior provides deterministic reset timing for FPGAs and microcontrollers, eliminating need for external RC timers or supervisor ICs in tightly sequenced power architectures.

Can the MAX8557ETE+T be used with ceramic output capacitors only, and what ESR requirement applies?

Yes, the MAX8557ETE+T is fully stable with ceramic output capacitors alone, provided their equivalent series resistance (ESR) is ≤0.05Ω. The datasheet specifies 2×10µF low-ESR ceramics for 4A operation, and recommends COUT ≥20µF to limit transient overshoot to ≤40mV. No tantalum or electrolytic capacitors are required, simplifying layout and improving reliability in high-vibration environments.

What thermal design practices are mandatory to sustain 4A continuous output from the MAX8557ETE+T?

To sustain 4A continuous output, the MAX8557ETE+T's exposed paddle (EP) must be soldered to a solid GND plane with ≥9 thermal vias (12mil diameter, 1mil plating), and the PCB must provide ≥7.6cm×7.6cm copper area per JEDEC JESD51-7. Without this, junction temperature exceeds +150°C under worst-case (VIN=3.6V, VOUT=1.2V) conditions. Thermal vias must connect EP directly to inner GND layers - not signal layers - to achieve θJA < 30°C/W.

Does the MAX8557ETE+T support adjustable output voltages, and how is the feedback network configured?

Yes, the MAX8557ETE+T supports adjustable output from 0.5V to 3.4V using the FB pin, which regulates to 0.5V (±5mV). Set VOUT with a resistor divider: R1 from OUT to FB, R2 from FB to GND, where VOUT = 0.5V × (1 + R1/R2). R2 ≤1kΩ ensures light-load stability; typical values for 1.5V output are R1 = 2kΩ, R2 = 1kΩ. No compensation components are needed - internal compensation is optimized for 10–120µF output capacitance.