Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Transistors > FETs, MOSFETs > FETs, MOSFETs

STMicroelectronics STP8NM50

Name: STP8NM50
Brand: STMicroelectronics
SKU: STP8NM50
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: STP8NM50

Manufacturer:: STMicroelectronics

Category:: FETs, MOSFETs

Package:: TO-220-3

Datasheet:: STP8NM50.pdf

Description:: MOSFET N-CH 550V 8A TO220AB

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:7,587

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

STP8NM50 from STMicroelectronics is an N-channel 550V MDmesh™ Power MOSFET in TO-220 package, rated for 8A continuous drain current at 25°C, with 0.7Ω typical R_DS(on), 15 V/ns peak dv/dt capability, and 100% avalanche tested. It serves as a high-voltage switching device in offline SMPS, AC-DC adapters, and industrial motor control inverters.

For engineers reviewing the STP8NM50 datasheet, STP8NM50 pinout, STP8NM50 application, or STP8NM50 equivalent, key selection criteria include its 550V V_DSS, low gate charge (13 nC), robust unclamped inductive switching performance, and thermal resistance of 1.25°C/W (j-case), critical for high-reliability power conversion designs.

Technical Context

The STP8NM50 employs ST's MDmesh™ technology-combining multiple drain process with PowerMESH™ horizontal layout-to achieve low on-resistance while maintaining high voltage ruggedness. Its 15 V/ns dv/dt rating and 200 mJ single-pulse avalanche energy (E_AS) support reliable operation under fast transient and inductive switching stress.

Designed for hard-switched topologies, it features low input capacitance (415 pF C_iss), fast switching times (16 ns t_d(on), 6 ns t_f), and a gate threshold voltage of 3–5 V, enabling direct drive from standard 10 V gate drivers without level-shifting.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DSS	550 V - Withstands up to 550 V drain-source blocking voltage, suitable for 380–400 V DC bus applications.
R_DS(on)	0.7 Ω (typ) @ V_GS = 10 V - Enables low conduction loss at 8 A, reducing thermal load in TO-220 packages.
I_D (cont)	8 A @ T_C = 25°C - Supports medium-power switching up to ~2 kW in forced-air-cooled designs.
E_AS	200 mJ - Absorbs unclamped inductive energy without failure, critical for flyback and resonant converters.
dv/dt	15 V/ns - Resists false turn-on during high-slew-rate transients, improving noise immunity in EMI-sensitive systems.
Q_g	13 nC - Low total gate charge reduces driver power requirement and enables efficient 100–500 kHz operation.
R_th(j–case)	1.25 °C/W - Enables 100 W dissipation with ≤125°C junction rise over case, supporting compact heatsink design.

Pinout & Package

TO-220 package with vertical metal tab (drain-connected), three leads: Gate (pin 1), Drain (pin 2, tab), Source (pin 3). Mounting requires electrically isolated heatsink due to conductive tab.

Pin/Terminal	Circuit Role	Design Meaning
Pin 1	Gate	High-impedance MOSFET control terminal; requires <30 V gate-source swing and low-inductance routing to minimize ringing.
Pin 2 / Tab	Drain	Main high-voltage power terminal; electrically connected to metal tab-must be insulated from heatsink unless referenced to same potential.
Pin 3	Source	Power return path and gate reference node; carries full load current and must be routed with low inductance to ground plane.

Key Features

Feature	Design Value
100% avalanche tested	Guarantees ruggedness against unclamped inductive switching events without derating or external snubbers.
MDmesh™ technology	Delivers 0.7Ω R_DS(on) at 550 V-~30% lower on-resistance than conventional planar MOSFETs in same voltage class.
Low gate input resistance	3 Ω (measured at 1 MHz) minimizes gate oscillation risk and simplifies RC damping network design.
High dv/dt immunity	15 V/ns rating ensures stable operation in high-frequency, high-noise environments like PFC stages and half-bridge inverters.

Applications

AC-DC Switch-Mode Power Supplies

Industrial Motor Drives

Use Scenario: Primary-side switch in 100–500 W offline flyback or forward converters with universal AC input (85–265 VAC).

IC Role / Device Role / Timing Role: High-voltage power switch controlling energy transfer via PWM duty cycle; operates at 65–130 kHz.

Use Value: 550 V rating accommodates reflected output voltage + leakage spike margin; 200 mJ E_AS eliminates need for clamping circuits in cost-sensitive designs.

Use Scenario: Half-bridge leg in 3-phase inverter driving 0.5–2 kW induction motors in HVAC or pump controllers.

IC Role / Device Role / Timing Role: Main switching element handling DC bus voltage (300–400 V) and phase current; commutated at ≤20 kHz.

Use Value: 15 V/ns dv/dt immunity prevents spurious turn-on during cross-conduction; low Q_g enables efficient gate drive with integrated half-bridge drivers.

LED Streetlight Drivers

UPS Inverters

Use Scenario: Buck-boost or SEPIC stage regulating constant-current output for 50–150 W outdoor LED arrays.

IC Role / Device Role / Timing Role: High-side switch managing wide-input-range regulation; subjected to frequent line surges and thermal cycling.

Use Value: Avalanche ruggedness ensures long-term reliability under lightning-induced transients; TO-220 mechanical robustness supports extended field life.

Use Scenario: Output H-bridge in online double-conversion UPS delivering clean 230 VAC sine wave from 360–400 V DC bus.

IC Role / Device Role / Timing Role: Final power stage switch operating in soft-switched or quasi-resonant mode at 25–50 kHz.

Use Value: Low C_oss (88 pF) and fast trr (185 ns @ 25°C) reduce switching losses and improve efficiency above 90% at full load.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
STP9NK50Z	500 V V_DSS, 0.75 Ω R_DS(on), Zener-protected gate, higher Q_g (22 nC)	Limited to ≤380 V DC bus; gate protection adds robustness but increases drive complexity	Select when enhanced gate ESD immunity is required and voltage margin allows 500 V rating.
FQP8N50C	500 V V_DSS, 0.85 Ω R_DS(on), no avalanche rating, higher R_th(j–case) (1.5°C/W)	Not rated for repetitive avalanche; unsuitable for unclamped inductive loads without snubbers	Select only for cost-sensitive, low-stress linear or resistive switching where avalanche stress is absent.

Compared with STP9NK50Z and FQP8N50C, the STP8NM50 offers superior voltage margin (550 V), verified avalanche capability (200 mJ), and lower thermal resistance-making it the preferred choice for industrial-grade 400 V bus applications demanding long-term reliability under transient stress.

Availability

STP8NM50 is available at Aetrix Electronics and suitable for AC-DC power supplies, industrial motor drives, LED lighting ballasts, and UPS inverters requiring stable component supply and proven field reliability.

Supply support for STP8NM50 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.

The STP8NM50 belongs to ST's MDmesh™ high-voltage Power MOSFET product line, engineered specifically for high-efficiency, high-reliability switching in offline power conversion systems up to 500 W.

FAQ

Is STP8NM50 suitable for use in zero-voltage switching (ZVS) topologies?

Yes. Its low C_oss (88 pF) and fast reverse recovery (trr = 185 ns at 25°C) enable efficient resonant transitions in LLC and phase-shifted full-bridge converters. However, ZVS operation requires careful tuning of dead time and resonant tank parameters to ensure soft switching across full load range.

What is the maximum recommended gate resistor value for reliable switching?

A gate resistor of 4.7 Ω is specified in the datasheet for switching time characterization. For practical designs, 10–22 Ω is recommended to balance switching speed (minimizing losses) and gate ringing suppression. Values >47 Ω significantly increase turn-off time and may cause thermal overstress at high frequency.

Does STP8NM50 require a gate-to-source zener clamp?

No. The absolute maximum V_GS is ±30 V, and typical gate drive is 10–15 V. A zener clamp is unnecessary if the gate driver has controlled voltage rails and low-impedance routing. However, a 15 V zener is advisable in noisy environments or when using bootstrap drivers with poor regulation.

Can STP8NM50 replace STP8NK50 in existing designs?

Yes, with verification. STP8NK50 is a 500 V part with similar R_DS(on) and package. The STP8NM50 provides 50 V higher blocking voltage and improved avalanche rating-offering margin for surge-prone applications-but requires confirming layout clearance and thermal performance under worst-case V_DS conditions.

STP8NM50 Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: MDmesh™ II

Package/Case:: TO-220-3

Packaging:: Tube

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 550 V

Current - Continuous Drain (Id) @ 25°C:: 8A (Tc)

Drive Voltage (Max Rds On, Min Rds On):: 10V

Rds On (Max) @ Id, Vgs:: 800mOhm @ 2.5A, 10V

Vgs(th) (Max) @ Id:: 5V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 13 nC @ 10 V

Vgs (Max):: ±30V

Input Capacitance (Ciss) (Max) @ Vds:: 415 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 100W (Tc)

Operating Temperature:: -65°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220

STP8NM50 FAQ

1.How can I place an order for STP8NM50 through Aetrix?

Please submit a Request for Quotation (RFQ) for STP8NM50 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.

2.Are the price and stock information for STP8NM50 reliable?

The price and inventory of STP8NM50 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STP8NM50 is usually 5 days.

3.What payment methods are accepted for STP8NM50?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STP8NM50 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for STP8NM50?

STP8NM50 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your STP8NM50 order is processed, you will receive an email with the shipment details and tracking number.

Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.

5.How can I obtain technical support or documentation for STP8NM50?

For technical support, including STP8NM50 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STP8NM50 requirements.

6.How does Aetrix verify that STP8NM50 is sourced from the original manufacturer or authorized distributors?

All STP8NM50 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that STP8NM50 meets industry standards.

7.What is the process for return or replacement of STP8NM50?

All STP8NM50 units undergo pre-shipment inspection (PSI). If there is an issue with STP8NM50, returns or replacements are accepted under the following conditions:

1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.

2.The issue is reported within 90 days of delivery.

3.The STP8NM50 part is unused and in its original packaging.

Return procedure for STP8NM50:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-11 Comparator Circuit: Voltage Thresholds, Op-Amp Differences, LM393 and Practical Design

Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.

2026-09-10 Schmitt Trigger Explained: Hysteresis, Circuits, Inverters and Applications

Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …