Infineon Technologies IRFB31N20DPBF

Overview

IRFB31N20DPBF from Infineon Technologies is a 200 V, 31 A N-channel enhancement-mode Power MOSFET in TO-262 (I²PAK) package, optimized for high-frequency DC-DC converters with low gate-to-drain charge (Qgd = 33–65 nC) and fully characterized effective output capacitance (Coss_eff = 170 pF). It delivers RDS(on) ≤ 0.082 Ω at VGS = 10 V and supports active clamp reset forward converter topologies in 48 V telecom power systems.

For engineers reviewing the IRFB31N20DPBF datasheet, IRFB31N20DPBF pinout, IRFB31N20DPBF application, or IRFB31N20DPBF equivalent, key selection criteria include avalanche energy rating (EAS = 420 mJ), diode reverse recovery performance (trr = 200–300 ns, Qrr = 1.7–2.6 µC), thermal resistance (RθJC = 0.75 °C/W), and gate charge profile (Qg = 70–107 nC) for hard-switched SMPS design.

Technical Context

This HEXFET device employs planar vertical DMOS structure with optimized charge balance for reduced switching losses in high dv/dt environments (peak diode recovery dv/dt = 2.1 V/ns). Its fully characterized Coss across 1.0 V to 160 V enables accurate snubberless soft-switching analysis in resonant and quasi-resonant converters.

The integrated body diode exhibits low forward voltage (VSD ≤ 1.3 V at IS = 18 A, TJ = 25°C) and controlled reverse recovery, supporting synchronous rectification and bidirectional current flow in active clamp and LLC configurations without external freewheeling diodes.

Key Specifications

Pinout & Package

IRFB31N20DPBF uses the TO-262 (I²PAK) package with exposed drain pad for thermal and electrical connection. The 4-pin configuration provides dual drain terminals to reduce source inductance and improve current sharing in paralleled layouts.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage power switching applications.

Compared with STP31N20 and IXTP31N20P, IRFB31N20DPBF offers superior ZVS enablers (lower Qgd, validated Coss_eff) and guaranteed avalanche ruggedness-critical for active clamp reliability-while its TO-262 package delivers 25% lower junction-to-case thermal resistance than TO-220 alternatives.

Availability

IRFB31N20DPBF is available at Aetrix Electronics and suitable for telecom power supplies, active clamp forward converters, high-frequency isolated DC-DC modules, and server VRM high-side switches requiring stable component supply and long-term industrial lifecycle support.

Supply support for IRFB31N20DPBF 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 electronics, and industrial control ICs, with global manufacturing and quality certification to ISO/TS 16949 and IECQ QC 080000.

This device belongs to Infineon's HEXFET Power MOSFET product line, engineered specifically for high-efficiency, high-frequency switched-mode power conversion in telecom, server, and industrial power supplies.

FAQ

What is the maximum continuous drain current at 100°C case temperature?

The IRFB31N20DPBF supports ID = 21 A continuous drain current at TC = 100°C with VGS = 10 V, as confirmed in the Absolute Maximum Ratings table. This derating reflects thermal limitations of the TO-262 package and must be applied when heatsink temperature exceeds 75°C in sustained operation.

Does this MOSFET require a negative gate turn-off voltage?

No. The gate threshold voltage range is 3.0–5.5 V, and gate-to-source voltage rating is ±30 V. A standard 0 V to +10 V gate drive suffices for full enhancement and safe turn-off; negative bias is unnecessary and not recommended per the datasheet.

Can IRFB31N20DPBF replace IRFS31N20DPbF in existing TO-220AB layouts?

No. Although electrically identical, IRFB31N20DPBF uses TO-262 (I²PAK) with different lead spacing, mounting hole pattern, and thermal pad geometry. Direct substitution requires PCB redesign; mechanical compatibility is not maintained between TO-220AB and TO-262 packages.

Is the body diode suitable for synchronous rectification?

Yes-the body diode is characterized for trr = 200–300 ns and Qrr = 1.7–2.6 µC at IF = 18 A and di/dt = 100 A/µs. These values support controlled commutation in synchronous rectifier circuits up to 300 kHz, provided gate timing accounts for Qrr-dependent reverse recovery tail.