Description:
Marked "K040N65Z" on the package (the "T" prefix is typically dropped in the on-body marking), this is Toshiba's TK040N65Z, a 650V n-channel enhancement mode power MOSFET in Toshiba's DTMOS VI series, designed to improve efficiency in high-speed switching power supplies. It's built in a standard through-hole TO-247 package with the classic 3-pin (Gate–Drain–Source) layout and mounting tab, well suited for high-power designs where a TO-220/TO-247 form factor with strong thermal performance is needed.
The part supports continuous drain current up to 57A and pulsed drain current up to 228A, with a typical RDS(ON) of 33mΩ. It also offers lower gate charge for faster switching, giving a roughly 40% lower figure of merit compared to earlier DTMOS-generation devices from Toshiba
Key Specifications
- Type: N-Channel Enhancement Mode Power MOSFET
- Manufacturer: Toshiba
- Package Marking: K040N65Z
- Package: TO-247, 3-pin, through-hole
- Drain-Source Voltage (VDSS): 650V
- Continuous Drain Current (ID): up to 57A
- Pulsed Drain Current: up to 228A
- RDS(ON), typical: 33mΩ
- Series: DTMOS VI (Toshiba's latest-generation deep-trench MOSFET process at time of release)
Common Applications
- Server power supplies
- Power conditioners in photovoltaic (solar) generators
- Uninterruptible power systems (UPS)
- High-speed switching power supplies generally (PFC stages, LLC/flyback converters, industrial SMPS)
Package Includes
- 1 x Toshiba TK040N65Z N-Channel Power MOSFET (TO-247)



