This post explains for the MOSFET.
The Part Number is K3683, 2SK3683.
The function of this transistor is 500V, 19A, N-Channel Power MOSFET.
Package: TO-220F15R type
Manufacturer: Fuji Electric
Preview images :
Description:
This is 500V, 0.38Ω, 19A, Power MOSFET.
K3683 datasheet
Features:
1. High Speed switching
2. Low on-resistance
3. Low driving power
1 page
Absolute Maximum Ratings :
1. Drain-Source Voltage : Vds = 500 V
2. Continuous Drain Current : Id = +- 19 A
3. Pulsed Drain Current : Id(pulse) = +- 76 A
4. Gate-Source Voltage : Vgs = +-30 V
5. Repetitive and Non-Repetitive Maximum Avalanche Current : Iar = 19 A
6. Non-Repetitive Maximum Avalanche Energy : Eas = 245.3 mJ
7. Maximum Power Dissipation: Pd ( Tc=25°C ) = 95 W
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Applications:
1. Switchig regulators
2. DC-DC converters
3. UPS