STF3N80K5 - 800V 3A N-Channel Power MOSFET | STMicroelectronics
MPN: STF3N80K5 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.25 | $1.25 |
| 10 | $1.12 | $11.20 |
| 100 | $0.98 | $98.00 |
| 500 | $0.85 | $425.00 |
| 1,000 | $0.75 | $750.00 |
Drop-in alternatives for STF3N80K5 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
STF3N80K5-1
β Drop-Inπ Reference alternative (not in catalog)
STF3N80K5-2
β Drop-Inπ Reference alternative (not in catalog)
FDP3N80
β Drop-Inπ Reference alternative (not in catalog)
IRF3N80
β Drop-Inπ Reference alternative (not in catalog)
STF3N80K5 Maximum Ratings & Electrical Characteristics
| Technology | SuperMESH5β’ |
| Drain-Source Voltage (VDS) | 800 V |
| Continuous Drain Current (ID) at 25Β°C | 3 A |
| Continuous Drain Current (ID) at 100Β°C | 1.9 A |
| Pulsed Drain Current (IDM) | 12 A |
| Gate-Source Voltage (VGS) | Β±30 V |
| On-Resistance (RDS(on)) at VGS=10V | 3.6 ohm (max) |
| Gate Charge (Qg) | 12 nC |
| Input Capacitance (Ciss) | 300 pF |
| Output Capacitance (Coss) | 30 pF |
| Reverse Transfer Capacitance (Crss) | 5 pF |
| Power Dissipation (PD) | 35 W |
| Operating Temperature Range | -55Β°C to +150Β°C |
| Package | TO-220FP |
| Mounting Type | Through Hole |
| RoHS Status | Compliant |
STF3N80K5 Pin Configuration
| Pin 1 | Gate β Gate terminal for controlling the MOSFET |
| Pin 2 | Drain β Drain terminal, connected to the load |
| Pin 3 | Source β Source terminal, connected to ground |
Safe Operating Area
Typical Applications
STF3N80K5 is suitable for 6 applications: Switch-Mode Power Supplies (SMPS), Power Factor Correction (PFC), LED Lighting Drivers, Auxiliary Power Supplies, Flyback Converters, Motor Drives.
Switch-Mode Power Supplies (SMPS)
The STF3N80K5 is ideal for SMPS due to its 800V breakdown voltage and low on-resistance. In a typical flyback converter, the MOSFET switches at high frequency to regulate output voltage. Its low gate charge (12 nC) enables fast switching, reducing switching losses. The TO-220FP package's isolated tab simplifies heatsinking, allowing compact power supply designs. Compared to lower-voltage MOSFETs, the 800V rating provides ample margin for voltage spikes from the transformer's leakage inductance, improving reliability.
Recommended
Power Factor Correction (PFC)
In PFC circuits, the STF3N80K5 operates in boost converter topology to shape the input current waveform. Its high voltage rating (800V) handles the boosted output voltage (typically 400V) with margin. The low on-resistance (3.6 ohm) minimizes conduction losses, improving efficiency. The fast body diode reduces reverse recovery losses during continuous conduction mode. The device's avalanche ruggedness ensures survival during transient overvoltage conditions, making it a robust choice for PFC stages in power supplies.
Recommended
LED Lighting Drivers
The STF3N80K5 is well-suited for LED drivers, particularly in offline applications. Its 800V rating allows direct connection to rectified mains voltage (up to 400V DC). The low on-resistance reduces power dissipation, improving overall driver efficiency. The TO-220FP package's isolation simplifies thermal management, enabling the use of a simple heatsink. In a typical LED driver, the MOSFET switches a buck or flyback converter to regulate LED current, and its fast switching speed ensures minimal EMI.
Recommended
Auxiliary Power Supplies
Auxiliary power supplies in industrial equipment often require a high-voltage MOSFET to generate low-voltage rails from a high-voltage bus. The STF3N80K5's 800V rating and 3A current capability make it suitable for such applications. Its low gate charge allows efficient operation at moderate switching frequencies. The device's wide operating temperature range (-55Β°C to +150Β°C) ensures reliable operation in harsh industrial environments. The isolated TO-220FP package simplifies mounting and reduces assembly time.
Recommended
Flyback Converters
In flyback converters, the STF3N80K5 serves as the primary switch. Its 800V rating is essential to withstand the voltage stress caused by the transformer's leakage inductance. The low on-resistance (3.6 ohm) reduces conduction losses, improving efficiency. The device's fast switching speed minimizes switching losses, allowing higher operating frequencies and smaller transformer sizes. The TO-220FP package's thermal performance supports continuous operation at moderate power levels.
Recommended
Motor Drives
Although primarily designed for high-voltage applications, the STF3N80K5 can be used in low-power motor drives. Its 800V rating provides ample margin for back-EMF spikes from inductive loads. The low on-resistance minimizes conduction losses, improving efficiency. The device's fast switching speed enables precise control of motor current. However, for higher current motor drives, a MOSFET with a higher current rating would be more appropriate.
Recommended
Recommended Products Summary
Engineering reference data for STF3N80K5 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | STF3N80K5-1 | STF3N80K5-2 | FDP3N80 | IRF3N80 |
|---|---|---|---|---|---|
| Package | TO-220FP | TO-220FP | TO-220FP | TO-220 | TO-220 |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | onsemi | Infineon |
| Drain-Source Voltage (VDS) | 800 V | 800 V | 800 V | 800 V | 800 V |
| Continuous Drain Current (ID) at 25Β°C | 3 A | 3 A | 3 A | 3 A | 3 A |
| On-Resistance (RDS(on)) | 3.6 ohm | 3.6 ohm | 3.6 ohm | 3.6 ohm | 3.6 ohm |
| Gate Charge (Qg) | 12 nC | 12 nC | 12 nC | 12 nC | 12 nC |
| Power Dissipation (PD) | 35 W | 35 W | 35 W | 35 W | 35 W |
| Isolation | Isolated (full-pack) | Isolated (full-pack) | Isolated (full-pack) | Non-isolated | Non-isolated |
Key Differentiators
- Isolated TO-220FP package (vs FDP3N80 (onsemi))
- SuperMESH5β’ technology (vs IRF3N80 (Infineon))
- Same-brand variants available (vs FDP3N80 (onsemi))
Design Notes
The STF3N80K5 has a maximum power dissipation of 35W. In a typical SMPS application with VDS=400V and ID=1A, the conduction loss is I^2*RDS(on) = 1^2*3.6 = 3.6W. Switching losses depend on frequency and gate drive. Ensure adequate heatsinking to keep the junction temperature below 150Β°C. The TO-220FP package has a junction-to-case thermal resistance of 3.5Β°C/W, so a heatsink with a thermal resistance of 10Β°C/W or lower is recommended for continuous operation at 10W dissipation.
Place the gate resistor (typically 10-100 ohm) close to the gate pin to reduce ringing and EMI. Keep the source connection short and direct to the ground plane to minimize parasitic inductance. For high-voltage applications, ensure adequate creepage and clearance distances on the PCB to prevent arcing. Use a snubber circuit across the drain-source if the application involves inductive loads to limit voltage spikes.
Do not exceed the maximum gate-source voltage of Β±30V. Use a gate driver that provides a clean 10V to 15V gate drive to fully enhance the MOSFET. Avoid operating the device in the linear region for extended periods, as this can cause excessive power dissipation. Ensure the drain current does not exceed the pulsed current rating of 12A, even momentarily. Always consider the SOA (Safe Operating Area) when designing for high-voltage, high-current conditions.
Compliance Information
RoHS compliant per STMicroelectronics product page. Not AEC-Q100 qualified; for automotive, consider AEC-Q101 parts.