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

Renesas 2SK3221-AZ

Name: 2SK3221-AZ
Brand: Renesas
SKU: 2SK3221-AZ
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: 2SK3221-AZ

Manufacturer:: Renesas

Category:: FETs, MOSFETs

Package:: -

Datasheet:: 2SK3221-AZ.pdf

Description:: N-CHANNEL POWER MOSFET

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Product details

Overview

2SK3221-AZ from Renesas Electronics is an N-channel enhancement-mode DMOS power MOSFET in an isolated TO-220 package, designed for high-voltage switching applications including offline AC-DC power supplies and AC adapters. It features 600 V drain-source breakdown voltage, 4.4 Ω maximum R_DS(on) at V_GS = 10 V and I_D = 1.0 A, 9 nC typical total gate charge, avalanche-rated operation, and ±30 V gate-source voltage tolerance.

For engineers reviewing the 2SK3221-AZ datasheet, 2SK3221-AZ pinout, 2SK3221-AZ application, or 2SK3221-AZ equivalent, key selection criteria include its 600 V blocking capability, low gate charge for fast switching, isolated package for enhanced creepage/clearance, avalanche energy rating (2.7 mJ), and suitability for discontinuous conduction mode (DCM) flyback and forward converters.

Technical Context

The 2SK3221-AZ employs a vertical DMOS structure optimized for high-voltage, medium-current switching with low gate drive requirements. Its gate threshold voltage range (2.5–3.5 V) enables reliable turn-on with standard 10 V logic-level drivers, while its 5 pF reverse transfer capacitance (C_rss) supports stable high-speed operation under hard-switching conditions.

Thermal performance is defined by R_th(j–c) = 5.0 °C/W and R_th(j–a) = 62.5 °C/W, requiring heatsinking for continuous 2.0 A DC operation. The integrated body diode exhibits 0.9 V forward voltage at 2.0 A and 0.9 µs reverse recovery time, enabling use in freewheeling and synchronous rectification auxiliary roles where diode recovery is non-critical.

Key Specifications

Parameter	Value and Actual Design Meaning
V_DSS	600 V - Supports primary-side switching in universal-input (85–265 VAC) offline SMPS without derating.
R_DS(on) max	4.4 Ω @ V_GS = 10 V, I_D = 1.0 A - Enables <1 W conduction loss at 1 A DC, suitable for ≤25 W power stages.
Q_G typ	9 nC - Reduces gate driver power demand and switching transition time in 50–100 kHz designs.
E_AS	2.7 mJ - Allows single-pulse inductive energy absorption without failure in flyback snubberless or clamp-free topologies.
I_D(pulse)	±8.0 A (PW ≤ 10 µs, duty ≤ 1%) - Supports peak current handling during startup or overload in current-mode controlled converters.
C_iss	290 pF - Defines input capacitance seen by gate driver; compatible with standard bipolar or CMOS gate drivers.
T_ch max	150 °C - Sets junction temperature limit for thermal design; requires case temperature monitoring in sealed enclosures.

Pinout & Package

2SK3221-AZ uses the isolated TO-220 (MP-45F) package with creepage distance ≥5 mm between drain and source/ground pins. The metal tab is electrically connected to the drain terminal and must be insulated from heatsink unless referenced to high-side potential.

Pin/Terminal	Circuit Role	Design Meaning
1 (Left)	Gate	Control electrode; requires ≤±30 V drive; gate protection diode integrated but external ESD/clamp recommended.
2 (Center)	Drain	High-voltage output node; connected to metal tab; isolation allows direct mounting to grounded heatsink only if drain is ground-referenced.
3 (Right)	Source	Power return path; defines reference for gate drive; body diode anode connects here for freewheeling paths.

Key Features

Feature	Design Value
Isolated TO-220 package	Enables safe mounting to grounded heatsinks in high-side switch configurations without additional insulation.
Avalanche-rated operation	Guarantees single-pulse ruggedness up to 2.7 mJ, eliminating need for external clamping in many flyback designs.
Low Q_G/R_DS(on) ratio	Optimizes trade-off between switching loss (Q_G-driven) and conduction loss (R_DS(on)-driven) in 50–100 kHz SMPS.
Body diode with defined t_rr	0.9 µs reverse recovery time supports use as freewheeling diode in DCM forward converters with predictable timing.
Gate threshold voltage stability	V_GS(off) shift <0.5 V from −25 °C to 125 °C ensures consistent turn-on behavior across industrial temperature range.

Applications

AC-DC Adapter Primary Switch	Flyback Converter Main Switch
Use Scenario: 12 V/2 A wall adapter operating from 85–265 VAC input with DCM flyback topology. IC Role / Device Role / Timing Role: Primary-side power switch controlling energy transfer via transformer; operates at 65 kHz with zero-voltage switching assist. Use Value: 600 V V_DSS provides 2× safety margin over reflected output voltage + leakage spike; 4.4 Ω R_DS(on) limits conduction loss to <0.5 W at full load.	Use Scenario: 5 V/5 A open-frame power supply for set-top box with integrated PWM controller. IC Role / Device Role / Timing Role: Main switching element in self-oscillating or fixed-frequency flyback; handles 2 A peak drain current during burst mode. Use Value: 2.7 mJ E_AS absorbs leakage inductance energy without snubber, reducing component count and improving efficiency by ~0.8%.
Industrial AC-DC Power Supply	LED Driver High-Voltage Switch
Use Scenario: 24 V/1.5 A DIN-rail mounted power supply for PLC I/O modules. IC Role / Device Role / Timing Role: Primary switch in continuous conduction mode (CCM) forward converter with active clamp. Use Value: Isolated TO-220 package permits direct heatsink mounting to chassis ground while maintaining 600 V isolation; 9 nC Q_G reduces gate driver losses at 100 kHz.	Use Scenario: Constant-current LED driver for street lighting with 300 V bus and 120 V LED string. IC Role / Device Role / Timing Role: High-side switch regulating current through buck-derived topology with valley switching. Use Value: 600 V rating accommodates line transients on 277 VAC systems; 0.9 V body diode VF minimizes auxiliary winding losses during off-time.

AC-DC Adapter Primary Switch

Flyback Converter Main Switch

Use Scenario: 12 V/2 A wall adapter operating from 85–265 VAC input with DCM flyback topology.

IC Role / Device Role / Timing Role: Primary-side power switch controlling energy transfer via transformer; operates at 65 kHz with zero-voltage switching assist.

Use Value: 600 V V_DSS provides 2× safety margin over reflected output voltage + leakage spike; 4.4 Ω R_DS(on) limits conduction loss to <0.5 W at full load.

Use Scenario: 5 V/5 A open-frame power supply for set-top box with integrated PWM controller.

IC Role / Device Role / Timing Role: Main switching element in self-oscillating or fixed-frequency flyback; handles 2 A peak drain current during burst mode.

Use Value: 2.7 mJ E_AS absorbs leakage inductance energy without snubber, reducing component count and improving efficiency by ~0.8%.

Industrial AC-DC Power Supply

LED Driver High-Voltage Switch

Use Scenario: 24 V/1.5 A DIN-rail mounted power supply for PLC I/O modules.

IC Role / Device Role / Timing Role: Primary switch in continuous conduction mode (CCM) forward converter with active clamp.

Use Value: Isolated TO-220 package permits direct heatsink mounting to chassis ground while maintaining 600 V isolation; 9 nC Q_G reduces gate driver losses at 100 kHz.

Use Scenario: Constant-current LED driver for street lighting with 300 V bus and 120 V LED string.

IC Role / Device Role / Timing Role: High-side switch regulating current through buck-derived topology with valley switching.

Use Value: 600 V rating accommodates line transients on 277 VAC systems; 0.9 V body diode VF minimizes auxiliary winding losses during off-time.

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
STP6NK60ZFP	600 V, 0.72 Ω R_DS(on), 18 nC Q_G, TO-220FP (non-isolated)	Lower R_DS(on) but higher Q_G; requires insulating pad for grounded heatsink	Select when lower conduction loss dominates over gate drive complexity and isolation is not required.
IXTP50N10P	100 V, 0.022 Ω R_DS(on), 42 nC Q_G, TO-220	Not voltage-compatible; suited only for low-voltage DC-DC, not AC-DC primary side	Reject for 2SK3221-AZ replacement; insufficient V_DSS for offline applications.

Compared with STP6NK60ZFP and IXTP50N10P, the 2SK3221-AZ uniquely balances 600 V capability, moderate R_DS(on), low Q_G, and built-in isolation-making it optimal for cost-sensitive, space-constrained AC-DC adapters where heatsink grounding flexibility matters.

Availability

2SK3221-AZ is available at Aetrix Electronics and suitable for AC-DC power supplies, flyback converters, and industrial LED drivers requiring stable component supply and long-term obsolescence management.

Supply support for 2SK3221-AZ 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

Renesas Electronics Corporation is a Japanese semiconductor manufacturer formed in 2010 through the merger of NEC Electronics and Renesas Technology, specializing in microcontrollers, analog, power, and mixed-signal solutions.

The 2SK3221-AZ belongs to Renesas' legacy high-voltage discrete MOSFET product line, engineered specifically for reliability and ruggedness in offline switching power conversion applications across consumer and industrial markets.

FAQ

What is the maximum continuous drain current rating for the 2SK3221-AZ?

The 2SK3221-AZ has a DC drain current rating of ±2.0 A at T_C = 25°C. This value decreases with rising case temperature per the derating curve; at 100°C case temperature, the usable DC current drops to approximately 1.0 A. For reliable operation, thermal design must ensure the 2SK3221-AZ case temperature remains within limits using appropriate heatsinking.

Does the 2SK3221-AZ have built-in gate protection?

Yes, the 2SK3221-AZ integrates a gate-to-source protection diode to suppress electrostatic discharge (ESD), as shown in its equivalent circuit diagram. However, Renesas explicitly states that an external protection circuit is still required if voltages exceeding the ±30 V gate rating may occur in the application. Therefore, robust gate clamping (e.g., TVS diode) remains necessary for real-world 2SK3221-AZ designs.

Can the 2SK3221-AZ be used in avalanche mode repeatedly?

No-the 2SK3221-AZ is rated for single-pulse avalanche only, with specified I_AS = 2.0 A and E_AS = 2.7 mJ under defined test conditions (V_DD = 150 V, R_G = 25 Ω, starting T_ch = 25°C). Repetitive avalanche operation is not characterized or guaranteed. For topologies requiring repetitive clamping (e.g., active clamp forward), the 2SK3221-AZ should not be relied upon without additional validation beyond the datasheet limits.

What is the significance of the "AZ" suffix in 2SK3221-AZ?

The "AZ" suffix in 2SK3221-AZ denotes a specific manufacturing variant compliant with RoHS directives and lead-free assembly processes, as confirmed by Renesas' packaging and environmental documentation. It shares identical electrical specifications, thermal characteristics, and mechanical dimensions with the base 2SK3221 part, and is functionally interchangeable in all supported applications.

How does the body diode performance of the 2SK3221-AZ affect its use in flyback converters?

The 2SK3221-AZ body diode has a forward voltage of 0.9 V at 2.0 A and reverse recovery time of 0.9 µs. In flyback converters operating in discontinuous conduction mode (DCM), this diode conducts only briefly during the off-time and does not significantly impact efficiency. However, in quasi-resonant or valley-switching designs, its recovery behavior must be accounted for in snubber sizing and EMI filtering-making the 2SK3221-AZ best suited for standard DCM flyback rather than high-frequency QR implementations.

2SK3221-AZ Specifications

Product attributes: Attribute value

Manufacturer:: Renesas

Series:: *

Package/Case:: -

Packaging:: Bulk

Product Status:: Active

FET Type:: -

Technology:: -

Drain to Source Voltage (Vdss):: -

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

Drive Voltage (Max Rds On, Min Rds On):: -

Rds On (Max) @ Id, Vgs:: -

Vgs(th) (Max) @ Id:: -

Gate Charge (Qg) (Max) @ Vgs:: -

Vgs (Max):: -

Input Capacitance (Ciss) (Max) @ Vds:: -

FET Feature:: -

Power Dissipation (Max):: -

Operating Temperature:: -

Grade:: -

Qualification:: -

Mounting Type:: -

Supplier Device Package:: -

2SK3221-AZ FAQ

1.How can I place an order for 2SK3221-AZ through Aetrix?

Please submit a Request for Quotation (RFQ) for 2SK3221-AZ 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 2SK3221-AZ reliable?

The price and inventory of 2SK3221-AZ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 2SK3221-AZ is usually 5 days.

3.What payment methods are accepted for 2SK3221-AZ?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 2SK3221-AZ transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 2SK3221-AZ?

2SK3221-AZ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 2SK3221-AZ 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 2SK3221-AZ?

For technical support, including 2SK3221-AZ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 2SK3221-AZ requirements.

6.How does Aetrix verify that 2SK3221-AZ is sourced from the original manufacturer or authorized distributors?

All 2SK3221-AZ 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 2SK3221-AZ meets industry standards.

7.What is the process for return or replacement of 2SK3221-AZ?

All 2SK3221-AZ units undergo pre-shipment inspection (PSI). If there is an issue with 2SK3221-AZ, 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 2SK3221-AZ part is unused and in its original packaging.

Return procedure for 2SK3221-AZ:

1.Submit a request within 90 days.

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

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