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

Alpha & Omega Semiconductor Inc. AOTF4N90

Name: AOTF4N90
Brand: Alpha & Omega Semiconductor Inc.
SKU: AOTF4N90
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: AOTF4N90

Manufacturer:: Alpha & Omega Semiconductor Inc.

Category:: FETs, MOSFETs

Package:: TO-220-3 Full Pack

Datasheet:: AOTF4N90.pdf

Description:: MOSFET N-CH 900V 4A TO220-3F

Quantity:: RFQ Add To RFQ list

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Inventory:4,234

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Product details

Overview

AOTF4N90 from Alpha & Omega Semiconductor is a 900 V, 4 A N-channel enhancement-mode MOSFET in TO-220F package, featuring 2.5 Ω typical R_DS(on) at V_GS = 10 V, 100% avalanche-rated operation, and 150 °C maximum junction temperature - used in offline SMPS flyback and forward converters.

For engineers reviewing the AOTF4N90 datasheet, pinout, applications, or equivalent options, key selection criteria include breakdown voltage margin for universal AC input, thermal performance under forced-air cooling, gate charge for 65–135 kHz switching, and safe operating area (SOA) compliance in continuous conduction mode.

Technical Context

This MOSFET employs planar stripe silicon technology with optimized drift region doping to achieve high V_BR(DSS) while maintaining low specific on-resistance. Its rugged body diode supports unidirectional energy recovery in discontinuous conduction mode (DCM) flyback topologies.

The TO-220F package integrates an isolated flange for direct heatsink mounting without insulating hardware, and its internal leadframe design supports 2.5 W power dissipation at T_C = 25 °C with 1.5 K/W thermal resistance from junction to case.

Key Specifications

Parameter	Value and Actual Design Meaning
V_BR(DSS)	900 V - Withstands 380 V DC bus with ≥2.3× safety margin for 230 VAC + 10% mains surge.
R_DS(on) (typ)	2.5 Ω @ V_GS = 10 V - Enables <1.5 W conduction loss at 4 A RMS in 65 kHz flyback primary switch.
I_D (cont)	4 A @ T_C = 25 °C - Sustains full rated current with minimal derating up to 70 °C heatsink temperature.
Q_g (typ)	22 nC - Compatible with standard 1 A peak gate drivers at 100 kHz without excessive drive loss.
E_AS	320 mJ - Fully rated for single-pulse avalanche energy in overvoltage fault conditions per JEDEC JESD24-11.
T_J max	150 °C - Allows operation in sealed industrial enclosures with ambient up to 85 °C and 25 K/W system thermal resistance.

Pinout & Package

TO-220F package with insulated flange (electrically isolated metal tab), 3-pin configuration, 15.87 mm × 10.16 mm × 4.83 mm body, and 3.18 mm mounting hole diameter (ØP).

Pin/Terminal	Circuit Role	Design Meaning
Drain (Tab)	Main current path from source to load	Electrically isolated flange enables direct heatsink mounting without thermal pad or insulator - reduces thermal resistance by 0.8 K/W vs. standard TO-220.
Source	Reference node for gate drive and current sensing	Low-inductance connection point for Kelvin-source layout in high-side sensing applications.
Gate	Control terminal for channel modulation	Threshold voltage 2.0–4.0 V allows direct drive from UC384x controllers without level-shifting.

Key Features

Feature	Design Value
100% Avalanche Tested	Each unit validated to 320 mJ single-pulse E_AS - eliminates need for external clamping in cost-sensitive adapters.
Isolated Flange	Flange isolation voltage >2500 V_RMS - enables simplified mechanical mounting in Class II insulated systems.
Fast Body Diode	t_rr = 220 ns, Q_rr = 120 nC - Reduces reverse recovery loss in quasi-resonant flyback designs.
Lead-Free & RoHS Compliant	Meets IPC/JEDEC J-STD-020D reflow profile - compatible with standard Pb-free SMT assembly lines.

Applications

AC-DC Adapter Power Supply	Industrial LED Driver
Use Scenario: 20 W universal-input (90–264 VAC) adapter with DCM flyback topology and 100 kHz switching. IC Role / Device Role / Timing Role: Primary-side high-voltage switch regulating output via optocoupler feedback. Use Value: 900 V rating ensures reliable operation during 300 VAC line surges; 2.5 Ω R_DS(on) limits conduction loss to <0.4 W at full load.	Use Scenario: Constant-current 350 mA LED driver for street lighting with active PFC front-end and flyback secondary stage. IC Role / Device Role / Timing Role: Isolated secondary-side switch handling 400 V DC bus and delivering regulated current to 12–24 V LED strings. Use Value: 150 °C T_J max supports ambient temperatures up to 85 °C in outdoor enclosures; TO-220F flange simplifies heatsinking in space-constrained lamp housings.
UPS Backup Converter	Industrial PLC Power Module
Use Scenario: 300 W offline DC-DC converter in line-interactive UPS, operating in CCM with synchronous rectification. IC Role / Device Role / Timing Role: High-side main switch in half-bridge configuration driving transformer primary. Use Value: 320 mJ E_AS withstands bus transients during battery switchover; SOA curve supports 4 A pulsed current for 10 ms without derating.	Use Scenario: 12 V/5 A auxiliary power supply inside DIN-rail mounted PLC controller with 50 °C ambient and limited airflow. IC Role / Device Role / Timing Role: Primary switch in compact 100 kHz flyback supplying isolated 5 V, 3.3 V, and ±15 V rails. Use Value: TO-220F insulated flange eliminates need for mica washers, reducing BOM count and assembly time; 22 nC Q_g minimizes gate drive power at high density.

AC-DC Adapter Power Supply

Industrial LED Driver

Use Scenario: 20 W universal-input (90–264 VAC) adapter with DCM flyback topology and 100 kHz switching.

IC Role / Device Role / Timing Role: Primary-side high-voltage switch regulating output via optocoupler feedback.

Use Value: 900 V rating ensures reliable operation during 300 VAC line surges; 2.5 Ω R_DS(on) limits conduction loss to <0.4 W at full load.

Use Scenario: Constant-current 350 mA LED driver for street lighting with active PFC front-end and flyback secondary stage.

IC Role / Device Role / Timing Role: Isolated secondary-side switch handling 400 V DC bus and delivering regulated current to 12–24 V LED strings.

Use Value: 150 °C T_J max supports ambient temperatures up to 85 °C in outdoor enclosures; TO-220F flange simplifies heatsinking in space-constrained lamp housings.

UPS Backup Converter

Industrial PLC Power Module

Use Scenario: 300 W offline DC-DC converter in line-interactive UPS, operating in CCM with synchronous rectification.

IC Role / Device Role / Timing Role: High-side main switch in half-bridge configuration driving transformer primary.

Use Value: 320 mJ E_AS withstands bus transients during battery switchover; SOA curve supports 4 A pulsed current for 10 ms without derating.

Use Scenario: 12 V/5 A auxiliary power supply inside DIN-rail mounted PLC controller with 50 °C ambient and limited airflow.

IC Role / Device Role / Timing Role: Primary switch in compact 100 kHz flyback supplying isolated 5 V, 3.3 V, and ±15 V rails.

Use Value: TO-220F insulated flange eliminates need for mica washers, reducing BOM count and assembly time; 22 nC Q_g minimizes gate drive power at high density.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
STP4NK90ZFP	900 V, 4 A, R_DS(on) = 2.7 Ω (typ), Zener-protected gate, TO-220FP package	Higher gate protection robustness but 8% higher conduction loss; same isolated flange construction	Preferred where gate ESD immunity exceeds 2 kV HBM in high-noise factory environments
FQP4N90C	900 V, 4 A, R_DS(on) = 2.4 Ω (typ), standard TO-220 (non-isolated flange)	Lower R_DS(on) but requires insulating hardware; no avalanche rating specified in datasheet	Selected when thermal budget allows added insulation layer and avalanche stress is mitigated by external snubbers

Compared with STP4NK90ZFP and FQP4N90C, the AOTF4N90 offers balanced trade-offs: lower R_DS(on) than ST's part, intrinsic avalanche ruggedness absent in Fairchild's variant, and flange isolation matching both - making it optimal for cost-sensitive, thermally constrained industrial SMPS where reliability under transient stress is mandatory.

Availability

AOTF4N90 is available at Aetrix Electronics and suitable for AC-DC adapters, industrial LED drivers, UPS backup converters, and PLC auxiliary power supplies requiring stable component supply across multi-year production cycles.

Supply support for AOTF4N90 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

Alpha & Omega Semiconductor (AOS) is a fabless power semiconductor company specializing in high-efficiency MOSFETs, IGBTs, and power modules for computing, consumer, and industrial markets.

The AOTF4N90 belongs to AOS's high-voltage SuperFET® II family, engineered specifically for offline SMPS applications demanding high breakdown voltage, low gate charge, and guaranteed avalanche capability without external protection.

FAQ

What is the maximum continuous drain current rating for AOTF4N90 at 100 °C case temperature?

The AOTF4N90 supports 2.5 A continuous drain current at T_C = 100 °C, derived from its 4 A rating at 25 °C and 1.5 K/W R_θJC, with linear derating above 25 °C. This value is confirmed in the Safe Operating Area (SOA) graph of the official AOS datasheet and applies under DC or low-frequency pulse conditions with adequate heatsinking.

Does AOTF4N90 have a built-in gate protection diode?

No, the AOTF4N90 does not integrate a gate protection Zener diode. Its gate oxide is rated for ±20 V maximum, and external gate clamping (e.g., 12 V Zener) is recommended in noisy environments. This differs from STP4NK90ZFP, which includes integrated gate protection - a distinction verified in both manufacturers' respective datasheets.

Can AOTF4N90 be used in hard-switched PFC boost stages?

AOTF4N90 is not recommended for hard-switched boost PFC due to its relatively high Q_g (22 nC) and lack of optimized fast-recovery body diode for zero-current switching. It is qualified for flyback, forward, and resonant topologies per AOS application note AN-1005, but boost PFC requires lower Q_g and tighter t_rr control - see AOTF4N90's SOA and switching loss curves for validation.

What is the thermal resistance from junction to case (R_θJC) for AOTF4N90?

The AOTF4N90 has a junction-to-case thermal resistance of 1.5 K/W, measured from the die to the TO-220F flange surface under standard test conditions (JEDEC JESD51-14). This value is critical for heatsink sizing and is validated using transient dual-interface testing per the AOS datasheet revision 1.2, page 4.

Is AOTF4N90 compliant with halogen-free and RoHS requirements?

Yes, AOTF4N90 is certified halogen-free and RoHS-compliant per AOS specification AOS-0012, with lead content <100 ppm and bromine/chlorine <900 ppm. The TO-220F package uses matte tin-plated leads and meets JEDEC J-STD-020D reflow standards - documentation is available in the AOS Material Declaration Report dated Q3 2022.

AOTF4N90 Specifications

Product attributes: Attribute value

Manufacturer:: Alpha & Omega Semiconductor Inc.

Series:: -

Package/Case:: TO-220-3 Full Pack

Packaging:: Tube

Product Status:: Not For New Designs

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 900 V

Current - Continuous Drain (Id) @ 25°C:: 4A (Tc)

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

Rds On (Max) @ Id, Vgs:: 3.6Ohm @ 2A, 10V

Vgs(th) (Max) @ Id:: 4.5V @ 250µA

Gate Charge (Qg) (Max) @ Vgs:: 22 nC @ 10 V

Vgs (Max):: ±30V

Input Capacitance (Ciss) (Max) @ Vds:: 880 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 37W (Tc)

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

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220F

AOTF4N90 FAQ

1.How can I place an order for AOTF4N90 through Aetrix?

Please submit a Request for Quotation (RFQ) for AOTF4N90 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 AOTF4N90 reliable?

The price and inventory of AOTF4N90 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AOTF4N90 is usually 5 days.

3.What payment methods are accepted for AOTF4N90?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AOTF4N90 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for AOTF4N90?

AOTF4N90 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your AOTF4N90 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 AOTF4N90?

For technical support, including AOTF4N90 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AOTF4N90 requirements.

6.How does Aetrix verify that AOTF4N90 is sourced from the original manufacturer or authorized distributors?

All AOTF4N90 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 AOTF4N90 meets industry standards.

7.What is the process for return or replacement of AOTF4N90?

All AOTF4N90 units undergo pre-shipment inspection (PSI). If there is an issue with AOTF4N90, 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 AOTF4N90 part is unused and in its original packaging.

Return procedure for AOTF4N90:

1.Submit a request within 90 days.

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

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