Infineon Technologies IR3812MTRPBF

Overview

IR3812MTRPBF from Infineon Technologies is a highly integrated synchronous buck regulator with integrated high- and low-side MOSFETs, delivering continuous 4A output current across 2.5V–21V input and 0.6V–12V output ranges. It operates at a fixed 600kHz switching frequency, features programmable over-current protection via OCSet pin, hiccup-mode current limiting, and supports pre-bias startup and voltage tracking for DDR memory termination (VTT). Used in graphics cards and server point-of-load rails.

For engineers reviewing the IR3812MTRPBF datasheet, IR3812MTRPBF pinout, IR3812MTRPBF application, or IR3812MTRPBF equivalent, key selection criteria include its thermally enhanced 5mm×6mm QFN-15 package, dual UVLO thresholds (VCC_UVLO: 4.0–4.4V, VC_UVLO: 3.1–3.5V), ±1.5% VFB accuracy over –40°C to +105°C, soft-start programmability, and integrated R_DS(on) current sensing (18–23mΩ top/bottom).

Technical Context

The IR3812MTRPBF implements voltage-mode PWM control with a fixed-frequency 600kHz oscillator and internal sawtooth ramp generation-no external timing components required. Its error amplifier compares FB (inverting) and VP (non-inverting) inputs against a precision 0.6V reference, enabling both standalone regulation and tracking mode when VP is driven externally.

Current limiting uses R_DS(on)-based sensing on the low-side MOSFET, eliminating external sense resistors. Protection includes non-latching thermal shutdown at 140°C (20°C hysteresis), hiccup-mode fault recovery, and independent UVLO monitoring of both VCC and VC supplies-ensuring safe operation during brown-out conditions.

Key Specifications

Pinout & Package

IR3812MTRPBF is housed in a thermally enhanced 5mm × 6mm Power QFN package with 15 exposed-pad terminals and wettable flanks for automated optical inspection. The exposed thermal pad must be soldered to a dedicated PCB thermal plane for junction-to-board thermal resistance ≤ 12°C/W.

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 TPS544B25RJER, the IR3812MTRPBF uniquely combines 4A integration, hardware-based VTT tracking, hiccup OCP, and thermally optimized 5×6mm QFN-making it optimal for cost-sensitive, space-constrained DDR and GPU VRM designs where analog simplicity and reliability are prioritized over digital control.

Availability

IR3812MTRPBF is available at Aetrix Electronics and suitable for graphics card VRMs, server DDR memory rails, and embedded point-of-load applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for IR3812MTRPBF 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 leader specializing in power management, automotive ICs, and industrial control solutions, with global manufacturing and quality certification to ISO/TS 16949 and IECQ QC 080000.

The IR3812 belongs to Infineon's SupIRBuck™ family-designed specifically for high-density, high-efficiency DC/DC conversion in computing and communications infrastructure where integration, thermal performance, and DDR compatibility are critical.

FAQ

What is the recommended minimum output capacitance for stable 4A operation at 600kHz?

Infineon specifies ≥22µF total ceramic output capacitance (X5R/X7R, 6.3V rating) placed within 5mm of the SW and PGnd pins. This ensures <15mVpp ripple under full load and maintains phase margin >45° with standard RC compensation on COMP. Larger values improve transient response but require verification of ESR/ESL impact on loop stability.

Can IR3812MTRPBF operate with VIN = 3.3V?

No-IR3812MTRPBF requires minimum VIN = 4.5V per Recommended Operating Conditions (Page 5). At 3.3V, VCC UVLO (4.0–4.4V) prevents startup, and VC cannot reach required VIN + 5V. For sub-4.5V inputs, consider Infineon's IR3836x series or external boost-buck architectures.

How is thermal performance affected if the exposed pad is not soldered to PCB copper?

Without thermal pad connection, θ_JA degrades from ≤12°C/W to >45°C/W, causing junction temperature to exceed 125°C at <2A load-even with 200LFM airflow. Soldering the pad to ≥250mm² internal/external copper pour with ≥4 thermal vias (0.3mm diameter, filled) is mandatory for 4A operation per datasheet layout guidelines.

Does IR3812MTRPBF support forced continuous conduction mode (FCCM)?

No-the IR3812MTRPBF operates exclusively in voltage-mode PWM with fixed 600kHz frequency and does not include pulse-skipping or FCCM modes. Light-load efficiency relies on reduced gate drive current and low quiescent ICC(Static) of 10–13mA; for burst-mode operation, consider Infineon's IR3897 or external controller solutions.