Infineon Technologies IRF6643TR1PBF

Overview

IRF6643TR1PBF from Infineon Technologies (formerly International Rectifier) is a 150 V, 35 A N-channel enhancement-mode MOSFET in DirectFET® MZ package, optimized for Class-D audio amplifier half-bridge output stages. It delivers 29 mΩ R_DS(on) at V_GS = 10 V, 39 nC total gate charge, and 0.9 Ω internal gate resistance to minimize THD, EMI, and conduction loss in high-fidelity digital audio systems.

For engineers reviewing the IRF6643TR1PBF datasheet, IRF6643TR1PBF pinout, IRF6643TR1PBF application, or IRF6643TR1PBF equivalent, key selection criteria include its low Q_rr (190–280 nC), dual-sided cooling capability, DirectFET® package inductance reduction, and validated performance delivering up to 200 W per channel into 8 Ω loads.

Technical Context

This MOSFET employs trench-gate silicon technology with optimized body diode reverse recovery (t_rr = 67–100 ns, Q_rr = 190–280 nC) and low stray inductance packaging to suppress voltage ringing during fast switching transitions in Class-D amplifiers. Its gate threshold voltage (V_GS(th) = 3.0–4.9 V) and transconductance (g_fs = 16 S) support stable PWM-driven half-bridge operation across -40°C to +150°C junction temperature range.

The DirectFET® MZ substrate enables PCB-mounted thermal transfer from both top and bottom copper layers, achieving R_θJC = 1.4°C/W and R_θJ-PCB = 1.0°C/W. Its 150 V V_(BR)DSS rating and 50 mJ single-pulse avalanche energy (E_AS) provide robustness against inductive kickback in unclamped inductive switching tests.

Key Specifications

Pinout & Package

IRF6643TR1PBF uses the DirectFET® MZ (Medium Can, Z-designation) surface-mount package: metal-can outline with top-side drain (D), bottom-side source (S), and edge-mounted gate (G) terminals. The package supports dual-sided cooling and is compatible with standard reflow soldering per AN-1035.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Class-D audio MOSFET applications.

Compared with IRF6643TR1PBF, the IRF6662TRPbF trades marginal gate charge increase for identical voltage/current ratings and package compatibility, whereas the STW48N60M2 belongs to a different voltage class and thermal architecture-making it unsuitable for space- and EMI-constrained audio amplifier designs.

Availability

IRF6643TR1PBF is available at Aetrix Electronics and suitable for high-fidelity home audio amplifiers, professional stage power modules, and automotive infotainment subwoofers requiring stable component supply and long-term production continuity.

Supply support for IRF6643TR1PBF 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 global semiconductor leader specializing in power management, sensor, and automotive ICs, with deep heritage in power MOSFET innovation following its acquisition of International Rectifier in 2015.

The DirectFET® product line was developed to replace wire-bonded packages in high-frequency power switching, targeting Class-D audio, server VRMs, and motor drives where low inductance and superior thermal performance are critical design requirements.

FAQ

What is the maximum recommended gate drive voltage for IRF6643TR1PBF?

The absolute maximum V_GS is ±20 V, but the device is characterized and optimized for 10 V gate drive. Using 12–15 V improves R_DS(on) margin at high temperature but increases Q_g-related switching loss and requires gate driver capable of 1.5 A peak current to achieve <20 ns rise time.

Can IRF6643TR1PBF be used in synchronous rectification mode?

Yes - its low Q_rr (190–280 nC) and soft-recovery body diode support synchronous rectification in Class-D output filters. However, external gate control timing must ensure dead-time ≥100 ns to prevent shoot-through, and PCB layout must minimize source inductance to avoid false turn-on.

Does IRF6643TR1PBF require a heatsink in a 200 W Class-D amplifier?

Not necessarily - with proper 2-oz copper PCB thermal pads (≥4 cm² per side) and airflow ≥1 m/s, the R_θJ-PCB = 1.0°C/W enables junction temperatures <110°C at 200 W. A heatsink is recommended only for sealed enclosures or ambient >50°C.

Is IRF6643TR1PBF pin-compatible with other DirectFET® MZ devices?

Yes - all DirectFET® MZ-outline MOSFETs (e.g., IRF6645, IRF6662) share identical mechanical footprint, pad layout, and terminal assignment (top drain, bottom source, edge gate), enabling drop-in replacement within the same voltage/current class when thermal and switching parameters align.