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

Vishay Siliconix IRFI744G

Name: IRFI744G
Brand: Vishay Siliconix
SKU: IRFI744G
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: IRFI744G

Manufacturer:: Vishay Siliconix

Category:: FETs, MOSFETs

Package:: TO-220-3 Full Pack, Isolated Tab

Datasheet:: IRFI744G.pdf

Description:: MOSFET N-CH 450V 4.9A TO220-3

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:9,539

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

Product details

Overview

IRFI744G from Vishay Siliconix is a 450 V, 4.9 A N-channel power MOSFET in TO-220 FULLPAK isolated package, featuring 0.63 Ω R_DS(on) at V_GS = 10 V, 80 nC total gate charge, and 2.5 kV_RMS isolation rating. It serves as a high-voltage switching device in offline SMPS, AC motor controls, and industrial power supplies where creepage and thermal management are critical.

For engineers reviewing the IRFI744G datasheet, IRFI744G pinout, IRFI744G application, or IRFI744G equivalent, key selection criteria include its isolated TO-220 FULLPAK package, 3.1 °C/W junction-to-case thermal resistance, avalanche energy rating of 130 mJ, and body diode reverse recovery time of 490–740 ns under specified test conditions.

Technical Context

This N-channel enhancement-mode MOSFET uses third-generation silicon technology optimized for fast switching and ruggedized operation in hard-switched topologies. Its isolated FULLPAK construction eliminates external insulation hardware while delivering 4.8 mm sink-to-lead creepage distance and low thermal resistance to heatsink.

The device supports unclamped inductive switching with repetitive avalanche current up to 4.9 A and single-pulse energy rating of 130 mJ. Dynamic dV/dt capability of 3.5 V/ns and integral body diode with 2.0 V forward drop at 8.8 A enable robust performance in flyback and resonant converters.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	450 V - Withstands full mains-referenced DC bus voltages in 230 VAC systems without derating
R_DS(on)	0.63 Ω @ V_GS = 10 V - Enables <1.5 W conduction loss at 2.9 A continuous drain current
Q_g	80 nC - Determines gate drive power requirement and switching speed in hard-switched circuits
I_D (T_C = 25 °C)	4.9 A - Maximum continuous current with case temperature maintained at 25 °C
R_thJC	3.1 °C/W - Enables efficient heat transfer from die to heatsink, reducing thermal bottleneck
E_AS	130 mJ - Supports reliable operation during unclamped inductive turn-off events
V_GS(th)	2.0–4.0 V - Ensures stable turn-on with standard 10 V gate drivers and immunity to noise-induced false triggering

Pinout & Package

IRFI744G is housed in a TO-220 FULLPAK package with electrically isolated tab, enabling direct mounting to heatsink without insulating washers. The package provides 2.5 kV_RMS isolation (60 s, 60 Hz) and 4.8 mm creepage between drain and source terminals.

Pin/Terminal	Circuit Role	Design Meaning
G (Gate)	Control input	Receives voltage-controlled signal to modulate channel conductivity; requires ≤±20 V drive
D (Drain)	High-side power terminal	Connected to high-voltage DC bus; electrically isolated from tab and heatsink
S (Source)	Power return / reference node	Serves as common reference for gate drive and load return path; bonded to isolated tab

Key Features

Feature	Design Value
Isolated TO-220 FULLPAK	Eliminates need for mica insulators or thermal pads-reduces assembly cost and thermal interface resistance
2.5 kV_RMS isolation	Meets reinforced insulation requirements for Class I equipment per IEC 60950-1 and IEC 62368-1
Low R_thJC = 3.1 °C/W	Enables higher power density by minimizing temperature rise across package interface
Dynamic dV/dt rating = 3.5 V/ns	Prevents spurious turn-on during high-speed voltage transients in bridge-leg configurations
Body diode t_rr = 490–740 ns	Reduces switching losses and EMI in discontinuous conduction mode (DCM) flyback converters

Applications

Industrial Motor Drives	Offline Switch-Mode Power Supplies
Use Scenario: Single-phase AC induction motor control in HVAC blowers and pump controllers operating from 230 VAC mains. IC Role / Device Role / Timing Role: High-side switch in half-bridge topology, handling 450 V DC link voltage and 4.9 A peak load current. Use Value: Isolated FULLPAK enables direct heatsink mounting without insulation hardware, reducing BOM count and thermal resistance by >30 % vs. standard TO-220.	Use Scenario: Primary-side switching transistor in 65–100 W universal-input flyback converters for LED drivers and industrial sensors. IC Role / Device Role / Timing Role: Main power switch turning on/off 360–400 V DC bus at 65–130 kHz with unclamped inductive stress. Use Value: 130 mJ single-pulse avalanche energy rating ensures reliability during output short-circuit or overload conditions without snubber redesign.
AC-DC Adapters	Industrial Lighting Ballasts
Use Scenario: Compact 36 W AC-DC adapter for industrial instrumentation requiring reinforced isolation and low standby power. IC Role / Device Role / Timing Role: Primary-side MOSFET in quasi-resonant (QR) flyback, leveraging low Q_g and fast body diode for valley switching. Use Value: 80 nC gate charge and 41 nC Q_gd support efficient QR operation with minimal dead-time penalty and reduced EMI.	Use Scenario: Electronic ballast for T5/T8 fluorescent lamps in factory lighting, operating from 230 VAC with active PFC front-end. IC Role / Device Role / Timing Role: Inverter-stage switch driving resonant tank at 25–50 kHz, subject to high dV/dt and body diode commutation. Use Value: 3.5 V/ns dV/dt rating and 2.0 V body diode forward voltage minimize false triggering and conduction loss during lamp ignition phase.

Industrial Motor Drives

Offline Switch-Mode Power Supplies

Use Scenario: Single-phase AC induction motor control in HVAC blowers and pump controllers operating from 230 VAC mains.

IC Role / Device Role / Timing Role: High-side switch in half-bridge topology, handling 450 V DC link voltage and 4.9 A peak load current.

Use Value: Isolated FULLPAK enables direct heatsink mounting without insulation hardware, reducing BOM count and thermal resistance by >30 % vs. standard TO-220.

Use Scenario: Primary-side switching transistor in 65–100 W universal-input flyback converters for LED drivers and industrial sensors.

IC Role / Device Role / Timing Role: Main power switch turning on/off 360–400 V DC bus at 65–130 kHz with unclamped inductive stress.

Use Value: 130 mJ single-pulse avalanche energy rating ensures reliability during output short-circuit or overload conditions without snubber redesign.

AC-DC Adapters

Industrial Lighting Ballasts

Use Scenario: Compact 36 W AC-DC adapter for industrial instrumentation requiring reinforced isolation and low standby power.

IC Role / Device Role / Timing Role: Primary-side MOSFET in quasi-resonant (QR) flyback, leveraging low Q_g and fast body diode for valley switching.

Use Value: 80 nC gate charge and 41 nC Q_gd support efficient QR operation with minimal dead-time penalty and reduced EMI.

Use Scenario: Electronic ballast for T5/T8 fluorescent lamps in factory lighting, operating from 230 VAC with active PFC front-end.

IC Role / Device Role / Timing Role: Inverter-stage switch driving resonant tank at 25–50 kHz, subject to high dV/dt and body diode commutation.

Use Value: 3.5 V/ns dV/dt rating and 2.0 V body diode forward voltage minimize false triggering and conduction loss during lamp ignition phase.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
STP4NK50ZFP	500 V V_DS, 4.0 A I_D, 1.2 Ω R_DS(on), TO-220FP package (non-isolated)	Requires external insulation hardware; lower current rating limits power scalability	Preferred where higher breakdown voltage is prioritized over thermal performance and isolation simplicity
FQP4N50	500 V V_DS, 4.0 A I_D, 1.4 Ω R_DS(on), standard TO-220 (non-isolated)	No isolation; higher R_DS(on) increases conduction loss by ~120 % at rated current	Cost-sensitive designs accepting added insulation complexity and higher thermal resistance

Compared with STP4NK50ZFP and FQP4N50, the IRFI744G delivers superior thermal performance (3.1 °C/W vs. ≥4.5 °C/W), integrated isolation eliminating hardware, and lower R_DS(on)-making it optimal for space-constrained, thermally demanding industrial power stages where reliability and assembly efficiency are critical.

Availability

IRFI744G is available at Aetrix Electronics and suitable for industrial motor drives, offline switch-mode power supplies, and AC-DC adapters requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for IRFI744G 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 power MOSFETs, diodes, and optoelectronics with emphasis on ruggedness, thermal performance, and reliability.

The IRFI744G belongs to Vishay's third-generation isolated FULLPAK power MOSFET family, engineered specifically for high-voltage industrial switching applications where simplified thermal design and reinforced insulation are mandatory.

FAQ

What is the maximum continuous drain current for IRFI744G at 100 °C case temperature?

The IRFI744G supports a continuous drain current of 3.1 A when the case temperature is maintained at 100 °C. This derating reflects thermal limitations of the TO-220 FULLPAK package and ensures safe operation within the 150 °C maximum junction temperature limit. Designers must verify heatsink sizing and ambient conditions to sustain this current reliably in long-term operation. The IRFI744G datasheet specifies this value in the Absolute Maximum Ratings table under "Continuous Drain Current".

Does IRFI744G require external insulation when mounted to a heatsink?

No, the IRFI744G does not require external insulation when mounted to a heatsink because its TO-220 FULLPAK package features an electrically isolated tab rated for 2.5 kV_RMS isolation. This built-in isolation eliminates the need for mica washers or silicone pads, simplifying mechanical assembly and improving thermal transfer. The IRFI744G achieves this via proprietary molding compound that provides both high dielectric strength and low thermal resistance.

What is the typical body diode reverse recovery time of IRFI744G?

The typical body diode reverse recovery time (t_rr) of the IRFI744G is 490 ns, with a maximum of 740 ns under test conditions of T_J = 25 °C, I_F = 8.8 A, and dI/dt = 100 A/µs. This parameter directly impacts switching losses and EMI in flyback and resonant converters. The IRFI744G's t_rr is specified in the "Drain-Source Body Diode Characteristics" section of its datasheet.

Can IRFI744G be used in avalanche-rated applications?

Yes, the IRFI744G is rated for both repetitive and single-pulse avalanche operation. It supports 4.9 A repetitive avalanche current and delivers 130 mJ single-pulse avalanche energy under defined test conditions. These ratings allow the IRFI744G to safely absorb inductive energy during switching transients without external snubbers in properly designed circuits. The IRFI744G avalanche specifications are validated per JEDEC standards and documented in its Absolute Maximum Ratings table.

What is the gate threshold voltage range for IRFI744G?

The gate threshold voltage (V_GS(th)) of the IRFI744G ranges from 2.0 V to 4.0 V, measured at V_DS = V_GS and I_D = 250 µA. This range ensures reliable turn-on with standard 10 V gate drivers while providing noise immunity against false triggering in electrically noisy industrial environments. The IRFI744G's V_GS(th) is specified in the Static Characteristics table of its official Vishay datasheet (Document Number: 91157).

IRFI744G Specifications

Product attributes: Attribute value

Manufacturer:: Vishay Siliconix

Series:: -

Package/Case:: TO-220-3 Full Pack, Isolated Tab

Packaging:: Tube

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 450 V

Current - Continuous Drain (Id) @ 25°C:: 4.9A (Tc)

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

Rds On (Max) @ Id, Vgs:: 630mOhm @ 2.9A, 10V

Vgs(th) (Max) @ Id:: 4V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 80 nC @ 10 V

Vgs (Max):: ±20V

Input Capacitance (Ciss) (Max) @ Vds:: 1400 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 40W (Tc)

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

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220-3

IRFI744G FAQ

1.How can I place an order for IRFI744G through Aetrix?

Please submit a Request for Quotation (RFQ) for IRFI744G 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 IRFI744G reliable?

The price and inventory of IRFI744G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IRFI744G is usually 5 days.

3.What payment methods are accepted for IRFI744G?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IRFI744G transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for IRFI744G?

IRFI744G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your IRFI744G 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 IRFI744G?

For technical support, including IRFI744G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IRFI744G requirements.

6.How does Aetrix verify that IRFI744G is sourced from the original manufacturer or authorized distributors?

All IRFI744G 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 IRFI744G meets industry standards.

7.What is the process for return or replacement of IRFI744G?

All IRFI744G units undergo pre-shipment inspection (PSI). If there is an issue with IRFI744G, 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 IRFI744G part is unused and in its original packaging.

Return procedure for IRFI744G:

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 …