This post explains for the MOSFET.
The Part Number is K4145, 2SK4145.
The function of this semiconductor is N-Channel 60V, 84A, MOSFET.
The package is TO-220 Type
Manufacturer: NEC
Preview images :
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Description:
The K4145 is 60V, 84A, N-channel MOS Field Effect Transistor.
Features:
1. Low on-state resistance : RDS(on) = 10 mΩ MAX. (VGS = 10 V, ID = 42 A)
2. Low input capacitance : Ciss = 5300 pF TYP.
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Absolute Maximum Ratings (Ta = 25°C)
1. Drain to source voltage: VDSS = 60 V
2. Gate to source voltage: VGSS = ± 20 V
3. Drain current: ID = ± 84 A (Tc = 25°C)
4. Total Power Dissipation : Pt = 84 W (Tc = 25°C)
5. Channel temperature: Tch = 150 °C
6. Storage temperature: Tstg = -55 to +150 °C
Applications:
1. High Current Switching