STMicroelectronics STF14NM50N

Overview

STF14NM50N from STMicroelectronics is an N-channel 500 V, 320 mΩ (max) MDmesh™ II Power MOSFET in TO-220FP package, rated for 12 A continuous drain current at 25 °C and featuring 27 nC total gate charge, 816 pF input capacitance, and 100% avalanche tested ruggedness. It serves as a high-efficiency primary-side switch in offline SMPS, PFC stages, and industrial DC-DC converters.

For engineers reviewing the STF14NM50N datasheet, STF14NM50N pinout, STF14NM50N application, or STF14NM50N equivalent, key selection criteria include its low R_DS(on) × Q_g figure-of-merit (8.64 Ω·nC), 15 V/ns dv/dt immunity, 2.5 kV isolation rating, and validated unclamped inductive switching capability up to 172 mJ.

Technical Context

This device employs ST's second-generation MDmesh vertical strip architecture to minimize conduction loss and switching energy simultaneously. Its 285 mΩ typical R_DS(on) at V_GS = 10 V and 6 A, combined with 15 nC gate-drain charge (Q_gd), enables high-frequency operation in hard-switched topologies while maintaining SOA integrity.

The integrated body diode exhibits 1.6 V forward voltage at 12 A and 252 ns reverse recovery time under 100 A/μs di/dt - critical for reducing commutation losses in bridge configurations. Thermal resistance of 5 °C/W (junction-to-case) supports direct mounting to heatsinks without thermal interface material degradation concerns.

Key Specifications

Pinout & Package

STF14NM50N uses the TO-220FP (Full-Pak) package: insulated plastic case with internal dielectric barrier between drain tab and leads, enabling direct PCB mounting without insulating washers. The drain is connected to the metal tab (Pin 2), gate to Pin 1, and source to Pin 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STP14NM50N, STF14NM50N trades 3.6× higher junction-to-case thermal resistance for certified isolation and simplified compliance; versus IPP60R099C7, it offers proven ruggedness at the cost of 1.6× higher conduction loss - making it preferred for cost-sensitive, high-reliability industrial SMPS.

Availability

STF14NM50N is available at Aetrix Electronics and suitable for industrial AC-DC adapters, server power supplies, and uninterruptible power systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for STF14NM50N 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 automotive, industrial, and consumer markets.

STF14NM50N belongs to the MDmesh™ II high-voltage Power MOSFET product line, engineered specifically for high-efficiency, high-reliability offline power conversion in industrial and telecom infrastructure equipment.

FAQ

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

The STF14NM50N supports 8 A continuous drain current at T_C = 100 °C, as specified in Table 1 of DS6618 Rev 8. This derating reflects thermal limits imposed by the TO-220FP package's 5 °C/W R_thJC and maximum junction temperature of 150 °C. Operation above this current requires forced-air cooling or reduced ambient temperature.

Does STF14NM50N have an integrated body diode, and what are its key parameters?

Yes, it features a monolithic source-drain body diode rated for 12 A continuous and 48 A pulsed current. At 12 A and 25 °C, forward voltage is 1.6 V; reverse recovery time is 252 ns with 2.8 μC charge under 100 A/μs di/dt. These values are measured per Figure 13 and Table 7 in DS6618 Rev 8.

Can STF14NM50N replace STP14NM50N in existing designs without layout changes?

No - STF14NM50N uses TO-220FP (insulated tab), while STP14NM50N uses TO-220 (non-insulated tab). Direct replacement requires verifying creepage/clearance distances and removing any insulating hardware, as the drain tab is internally isolated in STF14NM50N but electrically exposed in STP14NM50N.

Is the 2.5 kV isolation rating applicable to all three leads simultaneously?

Yes, the 2.5 kV RMS insulation withstand voltage (V_ISO) is measured from all three leads (gate, source, drain) collectively to an external heatsink, per test condition in Table 1 (t = 1 s, T_C = 25 °C). This qualifies STF14NM50N for reinforced insulation in Class I power supplies meeting IEC 60950-1 and IEC 62368-1 standards.