Infineon Technologies IR3895MTRPBF

Overview

IR3895MTRPBF from Infineon Technologies is a 16A synchronous buck regulator with integrated high- and low-side MOSFETs, internal LDO, bootstrap diode, and PWM controller. It operates from 1.0V–21V input, delivers 0.5V–0.86×Vin output, supports up to 1.5MHz switching frequency, and features programmable power good, thermal shutdown, and pre-bias startup. Used in server point-of-load power delivery.

For engineers reviewing the IR3895MTRPBF datasheet, IR3895MTRPBF pinout, IR3895MTRPBF application, or IR3895MTRPBF equivalent, key selection criteria include its 16A continuous output capability, thermally compensated current limit, monotonic start-up, Vp tracking interface, and 5mm × 6mm PQFN package with 17-pin layout.

Technical Context

The IR3895 implements a voltage-mode PWM control architecture with feed-forward line regulation and an error amplifier featuring 100–120 dB DC gain, 20–40 MHz GBWP, and ±1.5% input offset. Its oscillator supports resistor-programmed (300–1500 kHz) or external synchronization (270–1650 kHz) with <200 ns sync pulse tolerance.

Protection logic includes hiccup-mode overcurrent with thermal compensation, UVLO on Vcc (4.0–4.4 V trip) and Enable (1.14–1.26 V), monotonic soft-start/stop via S_Ctrl, and dual-threshold PGood with tracking capability tied to Vp or Vsns. The Smart LDO improves efficiency across light-to-full load by regulating Vcc/LDO_out at 4.0–6.7 V depending on DCM mode and load.

Key Specifications

Pinout & Package

IR3895MTRPBF uses a 5 mm × 6 mm Power QFN (PQFN) package with exposed thermal pad, lead-free and RoHS-compliant. Pin numbering follows top-view layout with 17 terminals, including dedicated PGnd, separated signal ground (Gnd), and boot capacitor node (Boot–SW).

Key Features

Applications

Equivalent & Alternatives

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

Compared with MP8765GQ-Z and TPS53689TSSR, IR3895MTRPBF uniquely combines 16 A integration, Vp-based tracking, monotonic startup, and Smart LDO in a single 5×6 mm PQFN-making it optimal for space-constrained, sequenced POL designs where BOM reduction and thermal robustness are critical.

Availability

IR3895MTRPBF is available at Aetrix Electronics and suitable for server power delivery, telecom baseband cards, and storage controller boards requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for IR3895MTRPBF 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 9001 and IATF 16949.

The SupIRBuck™ product line targets high-efficiency, highly integrated DC/DC conversion for datacenter, networking, and communications infrastructure-emphasizing reduced board area, simplified design, and robust fault protection.

FAQ

What is the minimum input voltage required for reliable operation with internal LDO bias?

IR3895MTRPBF requires Vin ≥ 6.8 V for stable internal LDO operation. Below this, the LDO enters dropout, degrading Vcc regulation and potentially affecting gate drive strength and control loop stability. For sub-6.8 V inputs, an external 4.5–7.5 V bias must be applied to Vcc/LDO_Out, and PVin should be shorted to that supply.

How does the Vp pin function in tracking mode, and what external components are needed?

In tracking mode, Vp accepts an external reference voltage (e.g., from another regulator's output) to force IR3895's output to follow it with ±16 A sink/source capability. No external capacitor is required; Vp is left floating in normal operation. When active, Vref must be tied to GND, and PGood thresholds shift to track Vp instead of Vref.

Can IR3895MTRPBF synchronize to an external clock while operating at 1.5 MHz?

Yes - the Sync input (Rt/Sync pin) accepts external clocks from 270 kHz to 1650 kHz. At 1.5 MHz, ensure the external clock has clean edges, ≤200 ns pulse width, and is AC-coupled via a Schottky diode to avoid DC loading. The device locks within one cycle and maintains phase alignment without jitter accumulation.

What is the purpose of the separate PGnd and Gnd pins, and how should they be routed?

PGnd carries high di/dt return current from the power stage (MOSFETs, SW, Boot), while Gnd serves low-noise analog and control circuitry (error amp, reference, logic). They must connect to a common system ground plane at a single point near the IC's thermal pad to prevent noise coupling into feedback paths and ensure stable regulation.