STMicroelectronics STP20NM50FD

Overview

STP20NM50FD from STMicroelectronics is an N-channel 500 V, 20 A FDmesh™ Power MOSFET in TO-220 package with fast-recovery body diode, R_DS(on) ≤ 0.25 Ω at V_GS = 10 V, 100% avalanche tested, and optimized for ZVS phase-shift converters and bridge topologies.

For engineers reviewing the STP20NM50FD datasheet, STP20NM50FD pinout, STP20NM50FD application, or STP20NM50FD equivalent, this device is selected for high-voltage switching where low gate charge (38 nC), tight R_DS(on) distribution, and robust dv/dt capability (20 V/ns) are critical in industrial SMPS and resonant converters.

Technical Context

This MOSFET employs ST's FDmesh™ process to integrate a low-R_DS(on) silicon structure with an intrinsic fast-recovery body diode (t_rr = 245 ns, Q_rr = 2 nC), enabling efficient synchronous rectification and reduced switching losses in hard- and soft-switching topologies.

Its 500 V V_DSS, 20 A I_D rating at T_C = 25 °C, and 0.65 °C/W R_thj-case support high-power density designs; the 100% unclamped inductive switching (UIS) test ensures reliability under transient overloads up to 10 A I_AS and 700 mJ E_AS.

Key Specifications

Pinout & Package

STP20NM50FD uses the TO-220 package (3-pin, through-hole, isolated tab). Pin 1 = Gate, Pin 2 = Drain (tab-connected), Pin 3 = Source. The metal tab is electrically connected to the Drain, requiring insulated mounting hardware when mounted to a common heatsink.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STW20NM50 and IPP60R099C6, STP20NM50FD delivers optimal trade-off between cost, thermal footprint, and integrated fast-diode functionality for 500 V ZVS bridge designs-making it preferred for space-constrained industrial SMPS where diode co-location is mandatory.

Availability

STP20NM50FD is available at Aetrix Electronics and suitable for industrial SMPS, ZVS phase-shift converters, motor drive inverters, and UPS output stages requiring stable component supply and long-term manufacturability.

Supply support for STP20NM50FD 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.

This device belongs to ST's FDmesh™ Power MOSFET product line, engineered specifically for high-efficiency, high-reliability switching in resonant and hard-switched offline power supplies and motor control systems.

FAQ

What is the maximum continuous drain current for STP20NM50FD at 100 °C case temperature?

The maximum continuous drain current is 14 A at T_C = 100 °C, as specified in Table 2 of the datasheet. This derating reflects thermal limitations of the TO-220 package; operation above this current requires forced-air cooling or heatsink optimization to maintain T_j ≤ 150 °C.

Does STP20NM50FD require a negative gate voltage to prevent spurious turn-on?

No. Its 20 V/ns dv/dt rating and 3 V minimum gate threshold voltage (V_GS(th) = 3–5 V) provide inherent immunity to parasitic turn-on under typical board-layout conditions. A 0 V to 10 V gate drive is sufficient; negative bias is unnecessary unless operating in extreme EMI environments with >30 V/ns transients.

Can STP20NM50FD be paralleled with identical units for higher current handling?

Yes-its tight R_DS(on) distribution and positive temperature coefficient above 100 °C enable stable current sharing. Use matched gate resistors (±1%), symmetrical PCB layout, and shared heatsink to ensure thermal coupling; derate total current by 15% for reliability in continuous operation.

Is the body diode suitable for continuous freewheeling in synchronous rectification?

Yes-the integrated fast-recovery body diode has t_rr = 245 ns and Q_rr = 2 nC at 150 °C, making it suitable for synchronous rectification in phase-shifted full-bridge and LLC converters up to 200 kHz. However, for >25 A average diode current, thermal design must account for V_SD = 1.5 V forward drop.