Infineon Technologies IRF6665TR1

Overview

IRF6665TR1 from Infineon Technologies (formerly International Rectifier) is a 100 V, 19 A N-channel enhancement-mode power MOSFET in DirectFET™ SH package, optimized for Class-D audio amplifier output stages. It delivers 53 mΩ R_DS(on) at V_GS = 10 V, 8.7 nC total gate charge, and 37 nC body-diode reverse recovery charge - enabling high efficiency, low THD, and reduced EMI in compact, heatsink-free 100 W/channel (8 Ω) designs.

For engineers reviewing the IRF6665TR1 datasheet, IRF6665TR1 pinout, IRF6665TR1 application, or IRF6665TR1 equivalent, key selection criteria include its low-stray-inductance DirectFET™ packaging, dual-sided cooling capability, optimized Q_g/Q_rr trade-off for switching fidelity, and compatibility with standard SMT reflow processes per AN-1035.

Technical Context

This MOSFET employs trench-gate silicon technology with tightly controlled threshold voltage (3.0–5.0 V) and low internal gate resistance (1.9 Ω typ.) to support fast, stable switching at 400 kHz in half-bridge Class-D topologies. Its 130 pF effective output capacitance (C_oss-eff) and 29 pF reverse transfer capacitance (C_rss) minimize Miller-induced shoot-through risk.

The device integrates a robust body diode with 31 ns reverse recovery time and 1.3 V forward voltage at 5 A, enabling reliable synchronous rectification and unclamped inductive switching. Thermal design leverages 3.0 °C/W R_θJC and 1.4 °C/W R_θJ-PCB via direct-drain thermal path and metalized PCB mounting.

Key Specifications

Pinout & Package

IRF6665TR1 uses the DirectFET™ SH outline: a leadless, double-sided cooling package with exposed drain on the top surface and source/gate terminals on the bottom side. The package measures 4.8 mm × 3.8 mm × 0.9 mm (L × W × H), with no traditional leads - all connections are soldered directly to PCB pads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IRF6662TR1, the IRF6665TR1 provides critical 25 V headroom for transient suppression in ±45 V audio rails; versus STW48N65M5, it reduces gate drive loss by 80% and enables 2× higher switching frequency with lower THD.

Availability

IRF6665TR1 is available at Aetrix Electronics and suitable for high-fidelity home audio amplifiers, automotive infotainment power stages, and professional sound system modules requiring stable component supply, consistent parametric performance across production lots, and long-term lifecycle support.

Supply support for IRF6665TR1 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 headquartered in Munich, Germany, specializing in power management, sensor, and automotive ICs with over 30 years of MOSFET innovation.

The IRF6665TR1 belongs to Infineon's DirectFET™ audio-optimized MOSFET product line, engineered specifically to replace conventional SO-8 and DPAK devices in Class-D amplifier output stages where thermal density, EMI control, and THD minimization are system-critical.

FAQ

What is the maximum recommended gate drive voltage for IRF6665TR1?

The absolute maximum V_GS is ±20 V, but the device is characterized and optimized for 10 V gate drive in Class-D applications. Driving above 12 V yields diminishing R_DS(on) improvement while increasing gate oxide stress and ESD vulnerability. Recommended gate drive range is 8–12 V with 25 Ω series resistance to dampen ringing.

Can IRF6665TR1 be used in synchronous rectification topologies?

Yes - its body diode exhibits 31 ns t_rr, 1.3 V V_SD, and 37 nC Q_rr, making it suitable for synchronous rectification in DC-DC converters up to 300 kHz. However, its 100 V rating and low Q_g are over-specified for most SR applications; dedicated SR controllers should verify gate timing alignment with V_DS zero-crossing detection.

Does IRF6665TR1 require special PCB layout considerations beyond standard DirectFET™ guidelines?

Yes - the top-side drain pad must connect to ≥2 oz copper with ≥4 thermal vias (0.3 mm diameter) to inner ground/power planes. Gate traces must be <5 mm long, shielded from drain switching nodes, and routed over solid reference planes to minimize coupling. AN-1035 mandates 0.2 mm stencil aperture for the drain pad to avoid solder voiding.

How does the DirectFET™ SH package affect thermal measurement methodology?

Junction-to-case (R_θJC) is measured at the top drain surface, not the PCB. TC is defined as the temperature at the center of the top copper pad under 1.4 W/mm² power density. Standard IR thermography or fine-wire thermocouples (0.05 mm dia.) placed directly on the drain pad yield valid readings; infrared measurements require emissivity calibration for bare copper.