Infineon Technologies IR3889MTRPBFAUMA1

Overview

IR3889MTRPBFAUMA1 from Infineon is a fully integrated 30 A synchronous buck regulator with OptiMOS™ power stages, fast Constant On-Time (COT) control, 0.8 V ±0.5% reference voltage, and programmable switching frequency from 600 kHz to 2 MHz. It operates from 4.3–17 V input (or 2.0–17 V with external VCC), supports monotonic start-up, pre-bias start-up, and thermally compensated overcurrent protection - deployed in server point-of-load rails.

For engineers reviewing the IR3889MTRPBFAUMA1 datasheet, IR3889MTRPBFAUMA1 pinout, IR3889MTRPBFAUMA1 application, or IR3889MTRPBFAUMA1 equivalent, key selection criteria include its integrated FETs, COT stability with ceramic output capacitors, four selectable OCP thresholds, soft-start timing options, and dual-mode operation (FCCM/DEM) for light-load efficiency optimization.

Technical Context

The IR3889 implements a fast COT control architecture with adaptive on-time generation, enabling rapid transient response without loop compensation. Its internal LDO powers gate drivers and logic, supporting single-supply operation or extended PVin range via external VCC biasing.

It integrates high- and low-side OptiMOS™ MOSFETs with bootstrap diode, uses SW node sensing for zero-cross detection, and features digitally configurable protection including hysteresis-based OTP, latchable OVP/UVP, and thermally compensated current limit with four resistor-selectable thresholds.

Key Specifications

Pinout & Package

Package: 5 mm × 6 mm PQFN, 37-pin, exposed thermal pad (PGND-connected), RoHS2-compliant and halogen-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP8772GQ-Z and TPS546B24RVFR, the IR3889MTRPBFAUMA1 offers broader input flexibility (2.0 V min with VCC bias), analog configurability without software overhead, and proven thermal robustness in unventilated industrial enclosures - making it optimal for cost-sensitive, high-reliability analog POL designs.

Availability

IR3889MTRPBFAUMA1 is available at Aetrix Electronics and suitable for server CPU core rails, telecom baseband units, storage controller power, and datacom switch ASIC supplies requiring stable component supply across long production lifecycles.

Supply support for IR3889MTRPBFAUMA1 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive, and industrial control ICs, with global manufacturing and qualification infrastructure.

The IR3889 belongs to Infineon's OptiMOS™ IPOL family - designed specifically for high-current, low-voltage point-of-load conversion in space-constrained, thermally demanding infrastructure equipment.

FAQ

What is the minimum input voltage when using external VCC bias?

The IR3889MTRPBFAUMA1 supports PVin as low as 2.0 V when an external 3.3–5.5 V supply is applied to the VCC/LDO pin. This bypasses the internal LDO and enables operation below the 4.3 V single-supply minimum, critical for low-voltage intermediate bus architectures.

How does the thermally compensated overcurrent protection work?

The IR3889 measures die temperature via an internal sensor and dynamically adjusts the ILIM threshold resistor divider's effective gain. As junction temperature rises, the OCP trip point decreases proportionally - preventing false triggering during sustained high-temp operation while preserving fault coverage.

Can the IR3889 start up into a pre-biased output?

Yes. The IR3889 includes dedicated pre-bias start-up circuitry that disables the high-side FET until the feedback voltage rises above ~0.4 V, then gradually ramps output without forcing reverse current through the output capacitor - verified per JEDEC JESD22-A108H.

What is the purpose of the SS/Latch pin beyond soft-start timing?

The SS/Latch pin also configures fault response mode: when pulled high, overvoltage and undervoltage faults trigger latch-off shutdown; when pulled low, they initiate hiccup-mode recovery. This dual function simplifies system-level fault management without additional logic components.