Infineon Technologies IRF6668TR1PBF

Overview

IRF6668TR1PBF from Infineon Technologies is an N-channel DirectFET™ Power MOSFET optimized for primary-side switching and secondary-side synchronous rectification in isolated DC-DC converters operating with 36–60 V input. It delivers 12 mΩ R_DS(on) at V_GS = 10 V, 22 nC total gate charge, 80 V V_DSS, and supports dual-sided cooling in a low-profile (0.7 mm) MZ-outline package.

For engineers reviewing the IRF6668TR1PBF datasheet, IRF6668TR1PBF pinout, IRF6668TR1PBF application, or IRF6668TR1PBF equivalent, key selection criteria include conduction loss minimization in high-frequency bridge topologies, thermal performance under double-sided PCB heatsinking, avalanche ruggedness (E_AS = 100 mJ), and compatibility with standard SMT reflow profiles up to 260 °C.

Technical Context

This MOSFET employs HEXFET® silicon in a copper-can DirectFET MZ package, enabling ultra-low R_DS(on) and 1.4 °C/W junction-to-case thermal resistance. Its gate threshold voltage (V_GS(th) = 4.0 V typ.) and negative temperature coefficient of R_DS(on) support stable parallel operation in high-current power stages.

The device exhibits high dv/dt immunity (≥50 V/ns), low Q_gd/Q_gs2 ratio (7.8 nC / 1.6 nC), and fast switching (t_r = 13 ns, t_f = 23 ns) - critical for minimizing losses in 300–1000 kHz isolated converter topologies such as phase-shifted full-bridge and active-clamp forward.

Key Specifications

Pinout & Package

The IRF6668TR1PBF uses the DirectFET™ MZ outline - a surface-mount, copper-can package with exposed drain on top and bottom, no leads, and footprint compatible with SO-8 layouts. Height is ≤0.7 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar power MOSFET applications.

Compared with IRF6662TR1PBF and SiR626DP, the IRF6668TR1PBF uniquely balances lowest R_DS(on), dual-sided thermal path, and avalanche energy - making it optimal for high-efficiency, high-power-density isolated DC-DC converters where both electrical and thermal margins are simultaneously constrained.

Availability

IRF6668TR1PBF is available at Aetrix Electronics and suitable for telecom DC-DC bricks, server VRMs, and industrial PoE++ PSE systems requiring stable component supply across multi-year production cycles.

Supply support for IRF6668TR1PBF 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 and discrete devices.

The DirectFET™ product line was engineered specifically for high-frequency, high-efficiency power conversion - targeting isolated DC-DC topologies where thermal density and switching loss dominate system-level performance.

FAQ

What is the maximum recommended PCB copper area for optimal thermal performance?

The IRF6668TR1PBF achieves its rated R_θJC = 1.4 °C/W when mounted on a minimum-footprint full-size board with metalized backplane and small clip heatsink. For best results, use ≥1 in² (6.45 cm²) of 2-oz copper on both top and bottom layers, connected via ≥8 thermal vias (0.3 mm diameter) under the drain pads.

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

No. The IRF6668TR1PBF has a gate threshold voltage of 4.0 V (typical) and operates reliably with 0 V to 10 V gate drive. Negative turn-off is not required, though a small negative bias (−2 V) may improve noise immunity in high-dv/dt environments - provided the gate driver supports it and stays within ±20 V absolute maximum rating.

Can it be used in paralleled configurations?

Yes. Its negative R_DS(on) temperature coefficient (0.097 V/°C) and matched threshold voltage distribution enable stable current sharing. Use individual gate resistors (≥5 Ω) and symmetrical layout to minimize loop inductance; derate total current by 15% for thermal margin when operating ≥3 devices in parallel.

Is the body diode suitable for asynchronous rectification?

The integrated body diode has V_SD = 1.3 V (max) and t_rr = 51 ns (max), making it usable for low-duty-cycle asynchronous operation. However, for >100 kHz operation or >5 A average current, synchronous rectification is strongly preferred to avoid excessive conduction and recovery losses.