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

Vishay Siliconix IRF840ASPBF

Name: IRF840ASPBF
Brand: Vishay Siliconix
SKU: IRF840ASPBF
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: IRF840ASPBF

Manufacturer:: Vishay Siliconix

Category:: FETs, MOSFETs

Package:: TO-263-3, D2PAK (2 Leads + Tab), TO-263AB

Datasheet:: IRF840ASPBF.pdf

Description:: MOSFET N-CH 500V 8A D2PAK

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Product details

Overview

IRF840ASPBF from Vishay Siliconix is a 500 V, 8.0 A N-channel power MOSFET in D2PAK (TO-263) package, featuring 0.85 Ω R_DS(on) at V_GS = 10 V, 38 nC total gate charge, and 510 mJ single-pulse avalanche energy-designed for high-voltage switching in offline SMPS half-bridge topologies.

For engineers reviewing the IRF840ASPBF datasheet, IRF840ASPBF pinout, IRF840ASPBF application, or IRF840ASPBF equivalent, key selection criteria include its 500 V V_DS, 125 W P_D at T_C = 25 °C, 1.0 °C/W R_thJC, body diode t_rr of 422–633 ns, and dV/dt ruggedness up to 5.0 V/ns.

Technical Context

This device uses planar stripe DMOS technology with fully characterized avalanche capability and effective output capacitance (C_{oss eff.} = 56 pF), enabling robust unclamped inductive switching in hard-switched converters. Its gate threshold voltage (2.0–4.0 V) and low Q_gd/Q_gs ratio (2.0:1) support stable turn-on under noisy gate drive conditions.

The integrated body diode exhibits 2.0 V forward drop at 8.0 A and 25 °C, with controlled reverse recovery (Q_rr = 2.0–3.0 μC), making it suitable for freewheeling paths where diode conduction occurs during dead time in bridge configurations.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DS	500 V - supports 400 V DC bus designs with 25 % margin for line surges and ringing
R_DS(on)	0.85 Ω @ V_GS = 10 V - limits conduction loss to ≤ 54.4 W at 8 A continuous drain current
Q_g	38 nC - determines gate driver current requirement (~3.8 mA avg. for 100 kHz switching)
E_AS	510 mJ - enables reliable operation in unclamped inductive load transients without snubbers
R_thJC	1.0 °C/W - allows 125 W dissipation with ≤ 125 °C junction rise above case temperature
t_rr	422–633 ns - defines minimum dead time needed to prevent shoot-through in synchronous bridges
dV/dt rating	5.0 V/ns - ensures immunity to parasitic turn-on during high dv/dt commutation events

Pinout & Package

D2PAK (TO-263) surface-mount package with exposed drain pad for thermal and electrical connection; 3-pin configuration (G, D, S) with drain tab electrically connected to pin 2 and thermally coupled to PCB copper area.

Pin/Terminal	Circuit Role	Design Meaning
G (Gate)	Control electrode	Receives 10 V logic-level drive; 9.0 nC Q_gs sets Miller plateau duration
D (Drain)	High-side switch node	Connected to exposed metal tab; carries full load current and must be routed over large copper pour
S (Source)	Reference return path	Common node for gate drive reference and current sensing; low-inductance layout critical for EMI control

Key Features

Feature	Design Value
Low gate charge (Q_g = 38 nC)	Reduces gate driver power loss and simplifies drive circuit design for 50–200 kHz SMPS
Enhanced avalanche ruggedness (E_AS = 510 mJ)	Eliminates need for external clamping circuits in flyback and forward converter primary switches
Characterized C_{oss eff.} = 56 pF	Enables accurate soft-switching timing prediction in resonant LLC and phase-shifted full-bridge designs
Body diode t_rr = 422–633 ns	Supports controlled commutation in half-bridge freewheeling without excessive voltage overshoot
5.0 V/ns dV/dt immunity	Prevents false turn-on during high-speed switching in high-noise industrial power stages

Applications

Offline AC-DC SMPS	Uninterruptible Power Supply (UPS)
Use Scenario: Primary-side switch in 200–500 W two-transistor forward or half-bridge converters operating from rectified 375 V DC bus. IC Role / Device Role / Timing Role: High-voltage power switch controlling energy transfer via transformer primary winding; operates at 50–100 kHz with 50 % duty cycle. Use Value: 500 V rating accommodates 400 V nominal bus with 20 % surge margin; 125 W P_D enables compact heatsink design.	Use Scenario: Inverter stage switch in line-interactive UPS delivering 1 kVA output with battery backup. IC Role / Device Role / Timing Role: Bridge-leg switch handling bidirectional power flow between battery DC link and AC output; conducts during 50/60 Hz fundamental and harmonics. Use Value: Avalanche rating sustains short-circuit events during grid fault transitions; body diode Q_rr minimizes reverse recovery losses during polarity reversal.
Industrial Motor Drive Inverter	High-Voltage DC-DC Converter
Use Scenario: Phase-leg switch in 400 V DC bus 3-phase inverter driving 0.5–2 kW induction motors. IC Role / Device Role / Timing Role: Hard-switched IGBT replacement in low-cost variable-frequency drives; gated at 2–8 kHz PWM carrier frequency. Use Value: 8.0 A continuous current supports 1.5 kW motor loads; 1.0 °C/W R_thJC enables direct mounting to aluminum chassis without isolation pads.	Use Scenario: Primary switch in isolated 48 V to 380 V boost converter for energy storage systems. IC Role / Device Role / Timing Role: High-side switch in non-isolated boost topology; handles 10–20 A peak inductor current at 100 kHz. Use Value: Low Q_gd/Q_gs ratio improves gate drive stability under high dV/dt; 0.85 Ω R_DS(on) limits conduction loss to < 1.4 W at 4 A RMS.

Offline AC-DC SMPS

Uninterruptible Power Supply (UPS)

Use Scenario: Primary-side switch in 200–500 W two-transistor forward or half-bridge converters operating from rectified 375 V DC bus.

IC Role / Device Role / Timing Role: High-voltage power switch controlling energy transfer via transformer primary winding; operates at 50–100 kHz with 50 % duty cycle.

Use Value: 500 V rating accommodates 400 V nominal bus with 20 % surge margin; 125 W P_D enables compact heatsink design.

Use Scenario: Inverter stage switch in line-interactive UPS delivering 1 kVA output with battery backup.

IC Role / Device Role / Timing Role: Bridge-leg switch handling bidirectional power flow between battery DC link and AC output; conducts during 50/60 Hz fundamental and harmonics.

Use Value: Avalanche rating sustains short-circuit events during grid fault transitions; body diode Q_rr minimizes reverse recovery losses during polarity reversal.

Industrial Motor Drive Inverter

High-Voltage DC-DC Converter

Use Scenario: Phase-leg switch in 400 V DC bus 3-phase inverter driving 0.5–2 kW induction motors.

IC Role / Device Role / Timing Role: Hard-switched IGBT replacement in low-cost variable-frequency drives; gated at 2–8 kHz PWM carrier frequency.

Use Value: 8.0 A continuous current supports 1.5 kW motor loads; 1.0 °C/W R_thJC enables direct mounting to aluminum chassis without isolation pads.

Use Scenario: Primary switch in isolated 48 V to 380 V boost converter for energy storage systems.

IC Role / Device Role / Timing Role: High-side switch in non-isolated boost topology; handles 10–20 A peak inductor current at 100 kHz.

Use Value: Low Q_gd/Q_gs ratio improves gate drive stability under high dV/dt; 0.85 Ω R_DS(on) limits conduction loss to < 1.4 W at 4 A RMS.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
STP8NK50ZFP	500 V, 7.5 A, R_DS(on) = 0.95 Ω, Q_g = 35 nC, TO-220FP package	Lower current rating and higher R_DS(on); requires larger heatsink for same power level	Preferred when through-hole assembly and lower gate charge are prioritized over thermal performance
FQP50N06L	60 V, 50 A, R_DS(on) = 0.023 Ω, TO-220 package	Not voltage-compatible; unsuitable for >100 V applications due to 60 V V_DS limit	Only viable in low-voltage (<60 V) DC-DC converters where high current and ultra-low R_DS(on) dominate

Compared with STP8NK50ZFP, IRF840ASPBF offers superior thermal resistance (1.0 vs. 2.5 °C/W) and higher continuous current (8.0 vs. 7.5 A); compared with FQP50N06L, it provides 8.3× higher voltage rating but trades off conduction loss efficiency below 100 V.

Availability

IRF840ASPBF is available at Aetrix Electronics and suitable for offline AC-DC power supplies, uninterruptible power systems, and industrial motor inverters requiring stable component supply across multi-year production cycles.

Supply support for IRF840ASPBF 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 and passive components, specializing in high-reliability power MOSFETs, diodes, and optoelectronics for industrial, automotive, and computing markets.

The IRF840AS family targets high-voltage, medium-power switching applications where avalanche robustness, gate drive simplicity, and thermal performance outweigh ultra-low R_DS(on) requirements.

FAQ

What is the maximum continuous drain current rating for IRF840ASPBF at 100 °C case temperature?

The IRF840ASPBF has a maximum continuous drain current (I_D) of 5.1 A when the case temperature is maintained at 100 °C. This derating reflects thermal limitations of the D2PAK package and ensures junction temperature remains within the -55 to +150 °C operating range. At 25 °C case temperature, the rating increases to 8.0 A. The linear derating factor is 1.0 W/°C, meaning power dissipation must decrease by 1 watt per degree above 25 °C.

Does IRF840ASPBF have a fully characterized body diode, and what are its key parameters?

Yes, IRF840ASPBF includes a fully characterized integral body diode with V_SD = 2.0 V at I_S = 8.0 A and T_J = 25 °C, reverse recovery time (t_rr) of 422–633 ns, and reverse recovery charge (Q_rr) of 2.0–3.0 μC. These values are measured under standardized conditions (T_J = 25 °C, I_F = 8.0 A, dI/dt = 100 A/μs) and support accurate dead-time calculation in bridge topologies.

Can IRF840ASPBF be used in place of IRF840PbF, and what is the difference?

IRF840ASPBF is the lead (Pb)-free and halogen-free version of IRF840PbF, sharing identical electrical specifications, thermal performance, and pinout. The "AS" suffix denotes enhanced avalanche ruggedness and tighter parameter distributions, while "PbF" indicates RoHS-compliant termination. Both use the D2PAK package, and no PCB or schematic changes are required for substitution in new designs.

What is the gate threshold voltage range for IRF840ASPBF, and how does it affect drive requirements?

The gate threshold voltage (V_GS(th)) for IRF840ASPBF is specified from 2.0 V to 4.0 V at I_D = 250 μA. This range ensures reliable turn-on with standard 10 V gate drivers while avoiding unintended conduction from noise coupling. A 10 V drive guarantees full enhancement (R_DS(on) ≤ 0.85 Ω), whereas 5 V may yield partial conduction and higher losses-making 10 V the recommended minimum for efficient operation.

Is IRF840ASPBF suitable for zero-voltage switching (ZVS) resonant converters?

IRF840ASPBF supports ZVS operation due to its characterized C_iss = 1018 pF, C_oss = 155 pF, and C_{oss eff.} = 56 pF, which enable predictable resonant tank behavior. However, its relatively high Q_g (38 nC) and moderate dV/dt rating (5.0 V/ns) make it better suited for fixed-frequency hard-switched topologies than high-frequency LLC resonant converters where ultra-low Q_g devices are preferred.

IRF840ASPBF Specifications

Product attributes: Attribute value

Manufacturer:: Vishay Siliconix

Series:: -

Package/Case:: TO-263-3, D2PAK (2 Leads + Tab), TO-263AB

Packaging:: Tube

Product Status:: Active

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 500 V

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

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

Rds On (Max) @ Id, Vgs:: 850mOhm @ 4.8A, 10V

Vgs(th) (Max) @ Id:: 4V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 38 nC @ 10 V

Vgs (Max):: ±30V

Input Capacitance (Ciss) (Max) @ Vds:: 1018 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 3.1W (Ta), 125W (Tc)

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: TO-263 (D2PAK)

IRF840ASPBF FAQ

1.How can I place an order for IRF840ASPBF through Aetrix?

Please submit a Request for Quotation (RFQ) for IRF840ASPBF 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 IRF840ASPBF reliable?

The price and inventory of IRF840ASPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for IRF840ASPBF is usually 5 days.

3.What payment methods are accepted for IRF840ASPBF?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for IRF840ASPBF transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for IRF840ASPBF?

IRF840ASPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your IRF840ASPBF 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 IRF840ASPBF?

For technical support, including IRF840ASPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your IRF840ASPBF requirements.

6.How does Aetrix verify that IRF840ASPBF is sourced from the original manufacturer or authorized distributors?

All IRF840ASPBF 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 IRF840ASPBF meets industry standards.

7.What is the process for return or replacement of IRF840ASPBF?

All IRF840ASPBF units undergo pre-shipment inspection (PSI). If there is an issue with IRF840ASPBF, 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 IRF840ASPBF part is unused and in its original packaging.

Return procedure for IRF840ASPBF:

1.Submit a request within 90 days.

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

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