TK12A45D MOSFET — Specifications & Equivalents
Manufacturer: Commonly produced by Toshiba
About the TK12A45D
The TK12A45D is a MOSFET with a drain–source voltage (VDS) rating of 450 V and a continuous drain current (ID) of 12 A. It can dissipate up to 45 W and is rated to a junction temperature of 150 °C. It is supplied in the TO220SIS package.
At a glance
- Type: MOSFET
- Max drain–source voltage (VDS): 450 V
- Max continuous drain current (ID): 12 A
- Power dissipation (PD): 45 W
- Max junction temperature (TJ): 150 °C
- Package: TO220SIS
- Manufacturer: Commonly produced by Toshiba
Typical applications
With its 450 V drain–source rating the TK12A45D 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 ±30 V maximum; exceeding it punctures the gate oxide and destroys the device permanently.
Switching behaviour is characterised by an output capacitance (Coss) of 120 pF, which together with the gate drive determines switching loss and the practical upper frequency limit.
Choosing a replacement for the TK12A45D
A drop-in substitute for the TK12A45D should match its polarity and offer a drain–source rating of at least 450 V and a continuous drain current rating of at least 12 A.
Mechanically, check the replacement against the TO220SIS 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 TK12A45D?
The TK12A45D is a MOSFET (metal-oxide-semiconductor field-effect transistor). It is rated for 450 V drain-source and 12 A continuous drain current.
What is the maximum voltage of the TK12A45D?
The TK12A45D has a maximum drain-source voltage (Vds) of 450 V. Treat this as an absolute maximum and design with margin, especially when switching inductive loads.
How much current can the TK12A45D handle?
It is rated for 12 A of continuous drain current, with power dissipation limited to 45 W. Real-world capability depends on your heatsinking and ambient temperature.
What package does the TK12A45D come in?
It is listed in TO220SIS. Verify the pinout of the specific variant, as one outline can carry different pin assignments.
What can I use to replace the TK12A45D?
This page lists 17 candidate equivalents matched on electrical ratings and package. Any replacement should meet or exceed the original voltage, current and dissipation figures and use a compatible drive level.
Key Specifications
| Pd ⓘ - Maximum Power Dissipation | 45 W |
|---|---|
| |Vds|ⓘ - Maximum Drain-Source Voltage | 450 V |
| |Vgs|ⓘ - Maximum Gate-Source Voltage | 30 V |
| |Id| ⓘ - Maximum Drain Current | 12 A |
| Tj ⓘ - Maximum Junction Temperature | 150 °C |
| Cossⓘ - Output Capacitance | 120 pF |
| Package | TO220SIS |
| TK12A60WMOSFETs Silicon N-Channel MOS (DTMOS)TK12A60WTK12A60WTK12A60WTK12A60W1. Applications1. Applications1. Applications1. Applications Switching Voltage Regulators2. Features2. Features2. Features2. Features(1) Low drain-source on-resistance | RDS(ON) = 0.265 (typ.) by used to Super Junction Structure : DTMOS(2) Easy to control Gate switching(3) E |