Infineon Technologies IR3897MTRPBF

Overview

IR3897MTRPBF from Infineon Technologies is a 4A 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 smart LDO biasing. It operates from 1.0 V to 21 V input, delivers 0.5 V to 0.86×Vin output, and supports monotonic pre-bias startup in server point-of-load applications.

For engineers reviewing the IR3897MTRPBF datasheet, IR3897MTRPBF pinout, IR3897MTRPBF application, or IR3897MTRPBF equivalent, key selection criteria include thermally compensated hiccup-mode overcurrent protection, external synchronization capability, Vp tracking source/sink (±4 A), precision margining support, and 4 mm × 5 mm PQFN thermal performance.

Technical Context

The IR3897 implements a voltage-mode PWM controller with feed-forward line regulation and zero-crossing detection for adaptive dead-time control. Its error amplifier features 100–120 dB DC gain, 20–40 MHz GBWP, and ±1.5% input offset-enabling tight regulation across load transients.

Internal architecture integrates bootstrap diode, MOSFET drivers, and a smart LDO that supplies gate drive while optimizing light-load efficiency. Protection logic includes programmable power-good with tracking, overvoltage detection (115–125% Vref), and thermal shutdown at 150°C junction temperature.

Key Specifications

Pinout & Package

IR3897MTRPBF uses a 4 mm × 5 mm, 17-pin Power QFN package with exposed thermal pad (PD-97663). Pin numbering follows top-view orientation per datasheet Figure 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP2315GJ-Z and TPS544B20RJRT, IR3897MTRPBF uniquely combines 4 A capability, Vp-based tracking, analog margining, and integrated bootstrap diode in a thermally optimized 4 mm × 5 mm package-making it optimal for analog-sequenced, space-constrained server and telecom POL designs.

Availability

IR3897MTRPBF is available at Aetrix Electronics and suitable for server point-of-load regulation, telecom line card power, and storage controller power requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for IR3897MTRPBF 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 quality certification to ISO/TS 16949 and IECQ QC 080000.

The SupIRBuck™ product line delivers highly integrated DC/DC regulators targeting high-efficiency, space-constrained point-of-load applications in datacenter, networking, and telecom infrastructure where reliability and thermal performance are critical.

FAQ

What is the minimum input voltage supported by IR3897MTRPBF?

The IR3897MTRPBF supports a minimum PVin of 1.0 V when externally biased via Vcc/LDO_Out. For single-rail internal bias operation, minimum Vin is 5.0 V; below 6.8 V, the internal LDO enters dropout, reducing gate drive headroom and efficiency.

How does the Vp pin function in tracking mode?

In tracking mode, the Vp pin accepts an external voltage reference to coordinate startup/shutdown timing with other regulators. It sources or sinks up to ±4 A during transitions, enabling precise voltage ramp alignment without external op-amps or discrete circuitry.

Can IR3897MTRPBF operate without an external bootstrap capacitor?

No. A 100 nF ceramic capacitor must be placed between Boot and SW pins to charge the high-side gate driver. Omitting this capacitor causes immediate failure of the high-side MOSFET due to insufficient gate voltage, resulting in no output regulation.

What thermal derating applies above 85°C ambient?

Derating begins at T_A = 85°C per the θ_JA = 3.5°C/W specification. At 100°C ambient, maximum continuous output current drops to ~3.2 A assuming 2-layer PCB with 1 oz copper and standard thermal pad layout; full 4 A requires active airflow or enhanced copper pours.