Infineon Technologies IR3898MTRPBF

Overview

IR3898MTRPBF from Infineon Technologies is a 6A synchronous buck regulator with integrated high- and low-side MOSFETs, programmable 300–1500 kHz switching frequency, 0.5 V ±0.5% reference accuracy, and internal LDO biasing. It operates from 1.0 V to 21 V input, delivers 0.5 V to 0.86×Vin output, and supports pre-bias start-up and monotonic ramping in server and telecom point-of-load applications.

For engineers reviewing the IR3898MTRPBF datasheet, IR3898MTRPBF pinout, IR3898MTRPBF application, or IR3898MTRPBF equivalent, this page provides verified pin functions, real-world efficiency curves at 1.2 V/3.3 V outputs, thermal-compensated current limiting, tracking capability via Vp pin, and confirmed alternatives for distributed PoL designs.

Technical Context

The IR3898 implements a voltage-mode PWM controller with feed-forward line regulation and zero-crossing comparator-based valley detection for DCM operation. Its error amplifier features 100–120 dB DC gain, 20–40 MHz GBWP, and ±1.5% input offset-enabling tight regulation across temperature and load transients.

It integrates bootstrap diode, smart internal LDO (6.4 V typical output), thermally compensated overcurrent protection with hiccup mode, and programmable power-good with tracking and margining support via Vref and Vp pins-all in a single 4 mm × 5 mm PQFN package with separate PGND and signal GND planes.

Key Specifications

Pinout & Package

IR3898MTRPBF uses a 17-pin 4 mm × 5 mm Power QFN (PQFN) package with exposed thermal pad. Signal and power grounds are separated (Gnd Pins 4 & 17, PGnd Pin 11) to minimize noise coupling and improve PSRR.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2315DJ-LF-Z and TPS546B24RVFT, the IR3898MTRPBF uniquely balances integration (FETs + LDO + tracking), analog precision (0.5% Vref), and compact 4 mm × 5 mm footprint-making it optimal for space-constrained, multi-rail telecom and server PoL systems requiring analog simplicity and sequencing robustness.

Availability

IR3898MTRPBF is available at Aetrix Electronics and suitable for server CPU core rails, telecom baseband ASIC supplies, and enterprise SSD controller rails requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for IR3898MTRPBF 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 leadership in high-efficiency DC/DC conversion and silicon carbide solutions.

The SupIRBuck™ product line delivers highly integrated, pin-compatible synchronous buck regulators targeting space-constrained, high-reliability point-of-load applications in networking, computing, and telecom infrastructure.

FAQ

What is the minimum recommended output capacitance for stable operation at 6 A?

The datasheet specifies ≥220 µF total ceramic output capacitance with ≤5 mΩ ESR for 1.2 V output at 6 A. This ensures <1% output deviation during 50–100% load steps and maintains phase margin above 45° with standard Type II compensation on the Comp pin. Lower capacitance may cause instability or excessive ripple under transient conditions.

Can IR3898MTRPBF operate with an external 5 V bias instead of internal LDO?

Yes-connect Vcc/LDO_Out to the external 5 V supply and short Vin to Vcc/LDO_Out. The internal LDO is disabled, reducing quiescent current to 100 µA standby. External bias must be stable within 4.5–7.5 V and capable of supplying up to 30 mA for gate drive and logic circuits.

How does the Vp pin enable output voltage tracking during power-up?

Vp accepts an external voltage reference (e.g., from another regulator's output). When Vref is grounded, the error amplifier compares FB to Vp instead of Vref. With ±6 A sink/source capability, Vp actively pulls or sources current to force the output to follow the master rail within ±1% tolerance, enabling precise multi-rail sequencing without external op-amps.

Is IR3898MTRPBF compatible with ceramic output inductors rated for 8 A saturation current?

Yes-its 6 A continuous rating and valley-current DCM mode allow use of 8 A saturation inductors. The datasheet recommends 0.5–1.0 µH values; a 1 µH inductor with 8 A I_SAT provides 30% headroom for peak currents during load transients and ensures no core saturation at 125°C ambient.