12N25 MOSFET — Specifications & Equivalents
About the 12N25
The 12N25 is an N-channel MOSFET with a drain–source voltage (VDS) rating of 250 V, a continuous drain current (ID) of 12 A and an on-resistance (RDS(on)) of 0.34 Ω. It can dissipate up to 73 W and is rated to a junction temperature of 150 °C. It is available in TO-220 and TO-252 packages, so confirm the pinout of the exact variant you order.
At a glance
- Type: N-channel MOSFET
- Max drain–source voltage (VDS): 250 V
- Max continuous drain current (ID): 12 A
- On-resistance (RDS(on)): 0.34 Ω
- Power dissipation (PD): 73 W
- Max junction temperature (TJ): 150 °C
- Package: TO-220, TO-252
Typical applications
With its 250 V drain–source rating the 12N25 sits in the medium-high-voltage class of switching MOSFETs, typically found in telecom and industrial DC rails, boost and flyback converters, LED and backlight drivers and power-factor-correction stages. Common where the bus sits well above 100 V but below rectified mains.
Gate drive and switching notes
Keep gate–source voltage within the ±20 V maximum; exceeding it punctures the gate oxide and destroys the device permanently.
Switching behaviour is characterised by a rise time of 80 ns and an output capacitance (Coss) of 900 pF, which together with the gate drive determines switching loss and the practical upper frequency limit.
Choosing a replacement for the 12N25
A drop-in substitute for the 12N25 must be the same N-channel type and offer a drain–source rating of at least 250 V, a continuous drain current rating of at least 12 A and an on-resistance no higher than 0.34 Ω if efficiency and heat matter.
Mechanically, check the replacement against the TO-220 and TO-252 footprint and confirm the pin order — parts sharing a package outline do not always share a pinout.
Where the application switches inductive loads or runs near the voltage limit, keep extra headroom rather than choosing a part that only just meets the original numbers.
Frequently asked questions
What is the 12N25?
The 12N25 is an N-channel MOSFET (metal-oxide-semiconductor field-effect transistor). It is rated for 250 V drain-source and 12 A continuous drain current.
What is the maximum voltage of the 12N25?
The 12N25 has a maximum drain-source voltage (Vds) of 250 V. Treat this as an absolute maximum and design with margin, especially when switching inductive loads.
How much current can the 12N25 handle?
It is rated for 12 A of continuous drain current, with power dissipation limited to 73 W. Real-world capability depends on your heatsinking and ambient temperature.
What is the on-resistance of the 12N25?
On-resistance (Rds(on)) is 0.34 Ω. Multiply by the square of your load current to estimate conduction loss.
What package does the 12N25 come in?
It is listed in TO-220 and TO-252. Verify the pinout of the specific variant, as one outline can carry different pin assignments.
What can I use to replace the 12N25?
No verified equivalents are listed yet. Choose a part of the same polarity that meets or exceeds every rating above and shares a compatible package and pinout.
Key Specifications
| Type | MOSFET |
|---|---|
| Channel Type | N -Channel |
| Drain-Source Voltage (Vds) | 250 V |
| Gate-Source Voltage (Vgs) | 20 V |
| Drain Current (Id) | 12 A |
| Drain-Source On-Resistance (Rds) | 0.34 |
| Rise Time (tr) | 80 nS |
| Output Capacitance (Coss) | 900 pF |
| Junction Temperature (Tj) | 150 °C |
| Package | TO-220 TO-252 |
| Power Dissipation (Pd) | 73 W |
Equivalent & Replacement Parts
No verified equivalents are listed for 12N25 yet.