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 STF3HNK90Z

Name: STF3HNK90Z
Brand: STMicroelectronics
SKU: STF3HNK90Z
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: STF3HNK90Z

Manufacturer:: STMicroelectronics

Category:: FETs, MOSFETs

Package:: TO-220-3 Full Pack

Datasheet:: STF3HNK90Z.pdf

Description:: MOSFET N-CH 800V 3A TO220FP

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:2,994

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

Product details

Overview

STF3HNK90Z from STMicroelectronics is a Zener-protected N-channel SuperMESH™ Power MOSFET rated for 900 V drain-source voltage, 3 A continuous drain current at 25°C, and 0.35 Ω typical R_DS(on) at V_GS = 10 V. It features built-in gate-source Zener diodes (±30 V breakdown), 100% avalanche tested operation, and extremely high dv/dt capability (4.5 V/ns), designed for high-voltage switching in offline SMPS and industrial AC-DC converters.

For engineers reviewing the STF3HNK90Z datasheet, STF3HNK90Z pinout, STF3HNK90Z application, or STF3HNK90Z equivalent, this device requires attention to its TO-220FP package thermal resistance (R_thj-case = 5 °C/W), low gate charge (Q_g = 26 nC), and integrated ESD protection (3000 V HBM) when evaluating reliability in flyback or resonant converter topologies.

Technical Context

This MOSFET employs ST's optimized strip-based SuperMESH™ layout to simultaneously reduce R_DS(on) and enhance dv/dt immunity-critical for hard-switched 800 V+ applications. Its intrinsic capacitances are minimized (C_iss = 690 pF, C_oss = 71 pF), supporting efficient high-frequency operation while maintaining robust unclamped inductive switching performance (E_AS = 200 mJ).

The integrated back-to-back gate-source Zener diodes provide ±30 V clamping without external components, directly addressing gate oxide protection during transient events. Its safe operating area (SOA) is validated up to 12 A pulsed drain current with derating, and it operates across −55°C to +150°C junction temperature range with insulation withstand voltage of 2500 V DC.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DSS	900 V - supports primary-side switching in universal-input offline power supplies up to 400 VAC mains with margin.
R_DS(on)	0.35 Ω (typ) @ V_GS = 10 V - enables <1.6 W conduction loss at 3 A, suitable for thermally constrained TO-220FP layouts.
I_D (cont)	3 A @ T_C = 25°C - defines maximum steady-state current before thermal derating begins (0.2 W/°C beyond 25°C).
Q_g	26 nC - reduces gate drive power requirement and switching losses in 50–100 kHz SMPS designs.
dv/dt	4.5 V/ns - ensures immunity to parasitic turn-on in high-noise, fast-rising voltage environments like PFC stages.
E_AS	200 mJ - guarantees single-pulse avalanche ruggedness during transformer leakage energy dissipation.
V_ESD(G-S)	3000 V HBM - eliminates need for external gate protection in standard industrial assembly lines.

Pinout & Package

STF3HNK90Z uses the TO-220FP (Full-Pak) package: insulated plastic case with internal isolation between drain (tab) and mounting surface, enabling direct heatsink attachment without insulator washers. Pin 1 = Gate, Pin 2 = Drain (tab-connected), Pin 3 = Source.

Pin/Terminal	Circuit Role	Design Meaning
Pin 1	Gate	Control terminal; accepts 10 V logic-level drive; protected by integrated ±30 V Zener clamp.
Pin 2	Drain	Main high-voltage power terminal; electrically connected to metal tab; requires heatsink isolation only if chassis-ground referenced.
Pin 3	Source	Power return path and reference for gate drive; tied to local ground or negative rail in buck/flyback configurations.

Key Features

Feature	Design Value
Zener-protected gate	Integrated ±30 V gate-source Zener diodes eliminate external TVS requirements and reduce BOM count in cost-sensitive power supplies.
SuperMESH™ layout	Optimized strip geometry delivers 0.35 Ω R_DS(on) at 900 V while preserving >4.5 V/ns dv/dt immunity-enabling compact, high-efficiency HV designs.
100% avalanche tested	Each unit undergoes unclamped inductive switching validation to 200 mJ, ensuring field reliability in transformer-coupled topologies.
Low C_oss & C_rss	71 pF output capacitance and 14.4 pF reverse transfer capacitance minimize switching losses and improve EMI behavior in resonant converters.
ECOPACK® compliance	Lead-free second-level interconnect meets RoHS and JEDEC JESD97 standards, with marked eco-labeling on packaging for traceability.

Applications

Offline Flyback Converters

Industrial AC-DC Power Supplies

Use Scenario: Primary-side switch in 30–60 W universal-input (85–265 VAC) flyback converters for industrial sensors and PLC I/O modules.

IC Role / Device Role / Timing Role: High-voltage power switch handling 720 V peak drain stress during startup and line surges.

Use Value: 900 V rating and 200 mJ avalanche energy prevent failure during output short-circuit or transformer saturation events.

Use Scenario: Main switching element in 100 W open-frame AC-DC power supplies for factory automation controllers.

IC Role / Device Role / Timing Role: Hard-switched N-channel MOSFET operating at 65 kHz with gate drive sourced from UC384x controller.

Use Value: Low Q_g (26 nC) and minimal C_iss (690 pF) reduce driver losses and enable stable gate timing under load transients.

LED Driver Ballasts

High-Voltage DC-DC Isolators

Use Scenario: Constant-current switch in isolated LED driver ballasts for street lighting operating from 277 VAC line.

IC Role / Device Role / Timing Role: Primary-side switch managing 400–500 V DC bus with active dimming control via PWM gate modulation.

Use Value: Zener-protected gate withstands gate ringing induced by transformer leakage in quasi-resonant operation.

Use Scenario: Input-stage switch in 1 kV-rated DC-DC isolators used in battery management system (BMS) monitoring circuits.

IC Role / Device Role / Timing Role: High-side switch controlling energy transfer into isolation transformer with 2500 V DC insulation barrier.

Use Value: 2500 V DC insulation withstand voltage and TO-220FP creepage/clearance meet reinforced isolation requirements per IEC 61800-5-1.

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
STP3NK90Z	TO-220 package (R_thj-case = 1.38 °C/W); no integrated Zener diodes; same V_DSS/R_DS(on)/I_D ratings.	Requires external gate protection; better thermal performance but larger footprint and non-isolated tab.	Select when board space allows TO-220 and gate protection is already implemented externally.
FQP9N90C	900 V, 9 A, 0.85 Ω R_DS(on); TO-3P package; no Zener protection; higher current but higher conduction loss.	Suitable for higher-power designs (>60 W) where thermal mass compensates for lower efficiency.	Choose only if system demands >3 A continuous current and gate protection is added separately.

Compared with STP3NK90Z and FQP9N90C, STF3HNK90Z uniquely combines gate Zener protection, TO-220FP insulation, and optimized dv/dt immunity-making it the preferred choice for space-constrained, safety-critical 30–60 W industrial power supplies where gate reliability and creepage are design priorities.

Availability

STF3HNK90Z is available at Aetrix Electronics and suitable for offline flyback converters, industrial AC-DC power supplies, and high-voltage LED driver ballasts requiring stable component supply and long-term industrial lifecycle support.

Supply support for STF3HNK90Z 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 analog, microcontroller, power, and sensor solutions for industrial, automotive, and consumer markets.

The SuperMESH™ MOSFET product line targets high-voltage switching applications demanding both low R_DS(on) and high ruggedness-specifically engineered for offline SMPS, PFC stages, and industrial motor drives operating above 600 V.

FAQ

Is STF3HNK90Z pin-compatible with STP3HNK90Z?

No. STF3HNK90Z uses the TO-220FP package with insulated tab and pinout Gate-Drain-Source (1-2-3), whereas STP3HNK90Z uses standard TO-220 with non-insulated tab and identical pinout but different thermal and isolation characteristics. Mechanical mounting and PCB layout are not interchangeable.

What is the maximum safe operating temperature for continuous operation?

The maximum junction temperature is 150°C, and the device supports continuous operation up to that limit when thermal design maintains T_j ≤ 150°C. At T_C = 100°C, the continuous drain current derates to 1.89 A, as specified in Table 1 of the datasheet.

Does STF3HNK90Z require an external gate resistor for stability?

Yes-a gate resistor (typically 10–47 Ω) is required to dampen gate ringing and control switching speed. The device's low input capacitance (690 pF) and fast switching (t_r = 28 ns) make it sensitive to PCB layout inductance; improper gate drive impedance can cause oscillation or overvoltage stress.

Can STF3HNK90Z be used in synchronous rectification topologies?

No. STF3HNK90Z is a high-voltage N-channel MOSFET optimized for primary-side switching-not secondary-side synchronous rectification. Its 900 V rating, slow body diode recovery (t_rr = 494 ns), and lack of optimized low-threshold gate drive make it unsuitable for low-voltage, high-frequency SR applications.

STF3HNK90Z Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: SuperMESH™

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

Packaging:: Tube

Product Status:: Obsolete

FET Type:: N-Channel

Technology:: MOSFET (Metal Oxide)

Drain to Source Voltage (Vdss):: 800 V

Current - Continuous Drain (Id) @ 25°C:: 3A (Tc)

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

Rds On (Max) @ Id, Vgs:: 4.2Ohm @ 1.5A, 10V

Vgs(th) (Max) @ Id:: 4.5V @ 50µA

Gate Charge (Qg) (Max) @ Vgs:: 35 nC @ 10 V

Vgs (Max):: ±30V

Input Capacitance (Ciss) (Max) @ Vds:: 690 pF @ 25 V

FET Feature:: -

Power Dissipation (Max):: 25W (Tc)

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

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220FP

STF3HNK90Z FAQ

1.How can I place an order for STF3HNK90Z through Aetrix?

Please submit a Request for Quotation (RFQ) for STF3HNK90Z 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 STF3HNK90Z reliable?

The price and inventory of STF3HNK90Z are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for STF3HNK90Z is usually 5 days.

3.What payment methods are accepted for STF3HNK90Z?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for STF3HNK90Z transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for STF3HNK90Z?

STF3HNK90Z orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your STF3HNK90Z 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 STF3HNK90Z?

For technical support, including STF3HNK90Z datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your STF3HNK90Z requirements.

6.How does Aetrix verify that STF3HNK90Z is sourced from the original manufacturer or authorized distributors?

All STF3HNK90Z 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 STF3HNK90Z meets industry standards.

7.What is the process for return or replacement of STF3HNK90Z?

All STF3HNK90Z units undergo pre-shipment inspection (PSI). If there is an issue with STF3HNK90Z, 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 STF3HNK90Z part is unused and in its original packaging.

Return procedure for STF3HNK90Z:

1.Submit a request within 90 days.

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

Tech Hub

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 …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…