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

Vishay Siliconix IRFU420

Name: IRFU420
Brand: Vishay Siliconix
SKU: IRFU420
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: IRFU420

Manufacturer:: Vishay Siliconix

Category:: FETs, MOSFETs

Package:: TO-251-3 Short Leads, IPAK, TO-251AA

Datasheet:: IRFU420.pdf

Description:: MOSFET N-CH 500V 2.4A TO251AA

Quantity:: RFQ Add To RFQ list

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Product details

Overview

IRFU420 from Vishay Siliconix is a 500 V, 2.4 A N-channel enhancement-mode power MOSFET in straight-lead IPAK (TO-251) package, optimized for through-hole mounting in high-voltage switching applications such as AC-DC adapters, offline SMPS, and motor control circuits. It features 3.0 Ω R_DS(on) at V_GS = 10 V, 19 nC total gate charge, and repetitive avalanche rating up to 2.4 A.

For engineers reviewing the IRFU420 datasheet, IRFU420 pinout, IRFU420 application, or IRFU420 equivalent, key selection criteria include its 500 V drain-source breakdown voltage, 42 W maximum power dissipation at T_C = 25 °C, 3.0 Ω on-resistance, and suitability for ruggedized high-voltage flyback and forward converter topologies requiring unclamped inductive switching capability.

Technical Context

The IRFU420 employs third-generation planar vertical DMOS technology with optimized cell layout for fast switching and low conduction loss. Its gate threshold voltage range of 2.0–4.0 V ensures reliable turn-on with standard 10 V gate drive while maintaining noise immunity.

Designed for hard-switched high-voltage applications, it supports repetitive avalanche operation up to 4.2 mJ per pulse and exhibits 3.5 V/ns peak diode recovery dV/dt capability-critical for minimizing parasitic turn-on in transformer-coupled topologies.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	500 V - Supports primary-side switching in 230 VAC offline converters with ≥2× safety margin
R_DS(on)	3.0 Ω @ V_GS = 10 V - Enables <2.4 A continuous conduction with ≤17.3 W I²R loss at full current
Q_g	19 nC - Determines gate driver current requirement (~1.9 mA avg. for 100 kHz, 10 V swing)
I_D (continuous)	2.4 A @ T_C = 25 °C - Defines thermal design basis for heatsink sizing in PCB-mount configurations
E_AS	400 mJ - Allows safe energy absorption during unclamped inductive switching events without device failure
R_thJC	3.0 °C/W - Enables direct thermal path to heatsink; junction-to-case resistance governs max power under forced cooling
V_GS(th)	2.0–4.0 V - Ensures robust turn-on with standard logic-level gate drivers while avoiding spurious activation

Pinout & Package

IRFU420 uses the IPAK (TO-251AA) straight-lead through-hole package with gull-wing leads. The thermally enhanced plastic body includes an exposed drain pad on the bottom surface for direct PCB copper pour attachment.

Pin/Terminal	Circuit Role	Design Meaning
G	Gate	Control terminal; requires 10 V drive for full enhancement; input capacitance C_iss = 360 pF affects switching speed and driver sizing
D	Drain	High-voltage output node; electrically connected to exposed thermal pad; handles 500 V blocking and avalanche energy dissipation
S	Source	Power return path and reference for gate drive; internal source inductance L_S = 7.5 nH impacts diode reverse recovery behavior

Key Features

Feature	Design Value
Repetitive avalanche rated	Supports 2.4 A I_AR and 4.2 mJ E_AR per pulse-enables reliable operation in flyback snubberless designs
Dynamic dV/dt rating	3.5 V/ns peak diode recovery dV/dt tolerance prevents false turn-on during high-slew-rate commutation
Through-hole IPAK (TO-251)	Enables mechanical robustness and high-reliability solder joints in industrial power supplies subject to vibration or thermal cycling
Fast switching	8.0 ns turn-on delay + 8.6 ns rise time enables >200 kHz operation with minimal switching loss trade-off
Low Q_gd/Q_g ratio	13/19 = 68% - Reduces Miller effect, improving controllability during hard switching and reducing gate drive losses

Applications

AC-DC Adapter Primary Switch	Industrial Motor Control Driver
Use Scenario: 230 VAC input offline flyback converter delivering 12 V/2 A output in compact wall-wart enclosure. IC Role / Device Role / Timing Role: Primary-side high-voltage switch handling 500 V DC link and unclamped inductive energy during MOSFET turn-off. Use Value: Repetitive avalanche rating (E_AR = 4.2 mJ) eliminates need for external snubber, reducing BOM count and board area.	Use Scenario: Half-bridge gate driver stage controlling 24 V brushed DC motor in factory automation actuator. IC Role / Device Role / Timing Role: Low-side switching element in H-bridge with integrated body diode conducting freewheeling current. Use Value: Body diode reverse recovery time (t_rr = 260–520 ns) minimizes shoot-through risk during PWM dead-time transitions.
LED Driver for High-Bay Lighting	UPS Inverter Stage
Use Scenario: Constant-current buck-boost LED driver powering 100 W white LED array from 300 V DC bus. IC Role / Device Role / Timing Role: Main switching transistor regulating current through high-side buck-boost inductor. Use Value: 3.0 Ω R_DS(on) limits conduction loss to ≤17.3 W at 2.4 A, enabling natural convection cooling in sealed fixture housing.	Use Scenario: 1 kVA line-interactive UPS with DC-link chopper stage converting battery voltage to 380 V DC for inverter input. IC Role / Device Role / Timing Role: High-voltage chopper switch operating at 25 kHz with 500 V blocking capability. Use Value: 500 V V_DS rating provides 1.5× margin over 380 V DC-link, ensuring long-term reliability under transient overvoltage conditions.

AC-DC Adapter Primary Switch

Industrial Motor Control Driver

Use Scenario: 230 VAC input offline flyback converter delivering 12 V/2 A output in compact wall-wart enclosure.

IC Role / Device Role / Timing Role: Primary-side high-voltage switch handling 500 V DC link and unclamped inductive energy during MOSFET turn-off.

Use Value: Repetitive avalanche rating (E_AR = 4.2 mJ) eliminates need for external snubber, reducing BOM count and board area.

Use Scenario: Half-bridge gate driver stage controlling 24 V brushed DC motor in factory automation actuator.

IC Role / Device Role / Timing Role: Low-side switching element in H-bridge with integrated body diode conducting freewheeling current.

Use Value: Body diode reverse recovery time (t_rr = 260–520 ns) minimizes shoot-through risk during PWM dead-time transitions.

LED Driver for High-Bay Lighting

UPS Inverter Stage

Use Scenario: Constant-current buck-boost LED driver powering 100 W white LED array from 300 V DC bus.

IC Role / Device Role / Timing Role: Main switching transistor regulating current through high-side buck-boost inductor.

Use Value: 3.0 Ω R_DS(on) limits conduction loss to ≤17.3 W at 2.4 A, enabling natural convection cooling in sealed fixture housing.

Use Scenario: 1 kVA line-interactive UPS with DC-link chopper stage converting battery voltage to 380 V DC for inverter input.

IC Role / Device Role / Timing Role: High-voltage chopper switch operating at 25 kHz with 500 V blocking capability.

Use Value: 500 V V_DS rating provides 1.5× margin over 380 V DC-link, ensuring long-term reliability under transient overvoltage conditions.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
STP5NK50ZFP	500 V, 4.5 A, R_DS(on) = 1.4 Ω, TO-220FP package, Zener-protected gate	Higher current rating but larger footprint; lacks repetitive avalanche rating (only single-pulse E_AS = 420 mJ)	Preferred where higher continuous current is required and PCB space allows TO-220FP mounting
FQP4N50	500 V, 4.0 A, R_DS(on) = 1.8 Ω, TO-220 package, no avalanche rating	Lower on-resistance but no specified repetitive avalanche capability; higher thermal resistance (R_thJC = 3.5 °C/W)	Selected when cost sensitivity outweighs ruggedness requirements and thermal design accommodates higher R_thJC

Compared with STP5NK50ZFP and FQP4N50, the IRFU420 offers verified repetitive avalanche operation and IPAK through-hole reliability at the expense of higher R_DS(on), making it optimal for space-constrained, high-reliability 2–2.4 A high-voltage switching applications where unclamped inductive stress is routine.

Availability

IRFU420 is available at Aetrix Electronics and suitable for AC-DC adapters, industrial motor controllers, and LED lighting drivers requiring stable component supply across extended production lifecycles.

Supply support for IRFU420 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

Vishay Siliconix is a global leader in discrete semiconductors, specializing in high-performance MOSFETs, diodes, and optoelectronics with emphasis on ruggedness and reliability.

The IRFU420 belongs to Vishay's third-generation high-voltage power MOSFET family engineered for demanding offline power conversion applications where repetitive avalanche capability, fast switching, and thermal robustness are critical.

FAQ

What is the maximum continuous drain current rating for IRFU420 at 100 °C case temperature?

The IRFU420 has a maximum continuous drain current of 1.5 A at T_C = 100 °C, as specified in the Absolute Maximum Ratings table. This derating reflects thermal limitations of the IPAK package under sustained high-temperature operation and must be used for thermal design validation when ambient or heatsink conditions exceed 25 °C.

Does IRFU420 support gate drive voltages below 10 V, and what is its guaranteed turn-on threshold?

Yes, the IRFU420 has a gate-source threshold voltage (V_GS(th)) range of 2.0–4.0 V at I_D = 250 μA, meaning it begins conducting significantly above 2.0 V. However, full enhancement to its rated 2.4 A requires V_GS ≥ 10 V to achieve the specified 3.0 Ω R_DS(on); operation at 5 V yields substantially higher on-resistance and is not characterized for production use.

Can IRFU420 be used in parallel configurations, and what design considerations apply?

Yes, the IRFU420 is designed for ease of paralleling due to its positive temperature coefficient of R_DS(on), which promotes current sharing. To ensure stability, designers must match gate drive loop inductance, use individual gate resistors (≥10 Ω), and maintain symmetrical PCB layout with identical trace lengths and thermal coupling between devices.

What is the thermal resistance from junction to ambient for IRFU420 in a typical PCB-mount configuration?

In a standard 1" square FR-4 PCB mount, the IRFU420 has a maximum junction-to-ambient thermal resistance (R_thJA) of 50 °C/W. This value assumes 1 oz copper, no heatsink, and natural convection; actual performance improves with added copper area or forced airflow, and must be validated using the device's SOA curves.

Is IRFU420 lead-free and RoHS compliant, and what is its halogen status?

Yes, the IRFU420 is lead-free and RoHS compliant per EU Directive 2011/65/EU. Vishay documents it as halogen-free per material categorization standard 99912, meaning bromine and chlorine content are each below 900 ppm, and total halogens are below 1500 ppm-meeting IPC-4101D and JEDEC JS709 requirements.

IRFU420 Specifications

Product attributes: Attribute value

Manufacturer:: Vishay Siliconix

Series:: -

Package/Case:: TO-251-3 Short Leads, IPAK, TO-251AA

Packaging:: Tube

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 500 V

Current - Continuous Drain (Id) @ 25°C:: 2.4A (Tc)

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

Rds On (Max) @ Id, Vgs:: 3Ohm @ 1.4A, 10V

Vgs(th) (Max) @ Id:: 4V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 19 nC @ 10 V

Vgs (Max):: ±20V

Input Capacitance (Ciss) (Max) @ Vds:: 360 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 2.5W (Ta), 42W (Tc)

Operating Temperature:: -55°C ~ 150°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-251AA

IRFU420 FAQ

1.How can I place an order for IRFU420 through Aetrix?

Please submit a Request for Quotation (RFQ) for IRFU420 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 IRFU420 reliable?

The price and inventory of IRFU420 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IRFU420 is usually 5 days.

3.What payment methods are accepted for IRFU420?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IRFU420 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for IRFU420?

IRFU420 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your IRFU420 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 IRFU420?

For technical support, including IRFU420 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IRFU420 requirements.

6.How does Aetrix verify that IRFU420 is sourced from the original manufacturer or authorized distributors?

All IRFU420 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 IRFU420 meets industry standards.

7.What is the process for return or replacement of IRFU420?

All IRFU420 units undergo pre-shipment inspection (PSI). If there is an issue with IRFU420, 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 IRFU420 part is unused and in its original packaging.

Return procedure for IRFU420:

1.Submit a request within 90 days.

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

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