40P04 MOSFET — Specifications & Equivalents
About the 40P04
The 40P04 is a MOSFET with a drain–source voltage (VDS) rating of 40 V and a continuous drain current (ID) of 40 A. It can dissipate up to 65 W and is rated to a junction temperature of 150 °C. It is supplied in the TO252 package.
At a glance
- Type: MOSFET
- Max drain–source voltage (VDS): 40 V
- Max continuous drain current (ID): 40 A
- Power dissipation (PD): 65 W
- Max junction temperature (TJ): 150 °C
- Package: TO252
Typical applications
With its 40 V drain–source rating the 40P04 sits in the low-voltage class of switching MOSFETs, typically found in 12 V and 24 V automotive and industrial rails, synchronous buck converters, load switching and reverse-polarity protection and H-bridges for small motors.
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 an output capacitance (Coss) of 551 pF, which together with the gate drive determines switching loss and the practical upper frequency limit.
Choosing a replacement for the 40P04
A drop-in substitute for the 40P04 should match its polarity and offer a drain–source rating of at least 40 V and a continuous drain current rating of at least 40 A.
Mechanically, check the replacement against the TO252 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 40P04?
The 40P04 is a MOSFET (metal-oxide-semiconductor field-effect transistor). It is rated for 40 V drain-source and 40 A continuous drain current.
What is the maximum voltage of the 40P04?
The 40P04 has a maximum drain-source voltage (Vds) of 40 V. Treat this as an absolute maximum and design with margin, especially when switching inductive loads.
How much current can the 40P04 handle?
It is rated for 40 A of continuous drain current, with power dissipation limited to 65 W. Real-world capability depends on your heatsinking and ambient temperature.
What package does the 40P04 come in?
It is listed in TO252. Verify the pinout of the specific variant, as one outline can carry different pin assignments.
What can I use to replace the 40P04?
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 | 65 W |
|---|---|
| |Vds|ⓘ - Maximum Drain-Source Voltage | 40 V |
| |Vgs|ⓘ - Maximum Gate-Source Voltage | 20 V |
| |Id| ⓘ - Maximum Drain Current | 40 A |
| Tj ⓘ - Maximum Junction Temperature | 150 °C |
| Cossⓘ - Output Capacitance | 551 pF |
| Package | TO252 |
| TK40P04M1MOSFETs Silicon N-Channel MOS (U-MOS-H)TK40P04M1TK40P04M1TK40P04M1TK40P04M11. Applications1. Applications1. Applications1. Applications Switching Voltage Regulators Motor Drivers2. Features2. Features2. Features2. Features(1) High-speed switching(2) Low gate charge | QSW = 7.4 nC (typ.)(3) Low drain-source on-resistance: RDS(ON) = 8.5 m (t |