STMicroelectronics STF6N65K3

Overview

STF6N65K3 from STMicroelectronics is an N-channel 650 V, 5.4 A MDmesh K3 Power MOSFET in TO-220FP package, featuring 1.1 Ω typical R_DS(on), 100 mJ single-pulse avalanche energy, and 12 V/ns peak diode recovery dv/dt capability. It serves as a high-voltage switching device in offline SMPS, PFC stages, and industrial AC-DC converters.

For engineers reviewing the STF6N65K3 datasheet, STF6N65K3 pinout, STF6N65K3 application, or STF6N65K3 equivalent, key selection criteria include avalanche ruggedness, low C_oss (65 pF), fast reverse recovery (285 ns at 25 °C), Zener-protected gate, and TO-220FP's insulated case for simplified heatsinking.

Technical Context

This MDmesh K3 MOSFET employs an optimized vertical structure to reduce conduction and switching losses simultaneously. Its 880 pF C_iss, 12 pF Crss, and 33 nC total gate charge enable high-frequency operation up to 100 kHz in hard-switched topologies.

The device integrates a fast, soft-recovery body diode with 5.1 µC Q_rr and 14 A I_RRM at 25 °C, supporting quasi-resonant and ZVS designs. Its 4.17 °C/W R_thJC and 150 °C T_Jmax support continuous operation at elevated ambient temperatures with moderate heatsinking.

Key Specifications

Pinout & Package

TO-220FP (Type B) package with insulated tab: thermally conductive but electrically isolated case rated for 2.5 kV RMS insulation. Mounting hole diameter 3.0–3.2 mm; case height 10.0–10.4 mm; lead pitch 2.54 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STP6N65K3 and FDPF6N65T, STF6N65K3 uniquely combines certified 2.5 kV insulation, identical MDmesh K3 dynamic performance, and TO-220FP's mechanical robustness-making it optimal for safety-critical, field-deployed AC-DC systems requiring zero additional isolation hardware.

Availability

STF6N65K3 is available at Aetrix Electronics and suitable for industrial AC-DC adapters, server PSU primary switches, and outdoor LED streetlight drivers requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for STF6N65K3 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

STF6N65K3 belongs to the MDmesh K3 high-voltage MOSFET product line, engineered specifically for high-efficiency, high-reliability offline power conversion in 65–300 W applications where avalanche ruggedness and diode quality are critical.

FAQ

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

The STF6N65K3 supports 3 A continuous drain current at T_C = 100 °C, as specified in Table 1 of DS7091 Rev 3. This derating reflects thermal limits of the TO-220FP package and ensures safe operation within SOA boundaries at elevated ambient conditions.

Does STF6N65K3 require external gate protection?

No external gate protection is required under normal operation. The device integrates a bidirectional Zener clamp between gate and source, rated for ±30 V and validated for 2.5 kV HBM ESD. External clamping is only needed if gate drive exceeds ±30 V or in ultra-high-noise environments exceeding 12 V/ns.

How does the body diode performance compare to standard planar MOSFETs?

The STF6N65K3's body diode delivers 5.1 µC Q_rr and 285 ns t_rr at 25 °C-up to 40% lower Q_rr than comparable 650 V planar devices. Its soft recovery characteristic reduces EMI and eliminates need for external snubbers in PFC and flyback topologies.

Can STF6N65K3 be used in place of STP6N65K3 without layout changes?

No. Although electrically identical, STF6N65K3 uses TO-220FP (insulated tab) versus STP6N65K3's TO-220 (conductive tab). Mounting holes and creepage distances differ; PCB footprint and heatsink interface must be redesigned to accommodate 2.5 kV isolation and altered mechanical dimensions.