This post explains for the Transistor.
The Part Number is C5478, 2SC5478.
The function of this semiconductor is 900V, 50mA, NPN Transistor.
The package is TO-220AB type
Manufacturer: Sanyo Semicon Device
Preview images :
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Description
This is 900V, 50mA, NPN Triple Diffused Planar Silicon Transistor.
Features
1. High breakdown voltage
2. Small Cob
3. Wide ASO
4. High reliability ( Adoption of HVP process )
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Absolute maximum ratings ( Ta=25°C )
1. Collector to Base Voltage: Vcbo = 1700 V
2. Collector to Emitter Voltage: Vceo = 900 V
3. Emitter to Base Voltage: Vebo = 5 V
4. Collector Current: Ic = 50 mA
5. Collector Dissipation : Pc = 1.75 W
6. Junction Temperature: Tj = 150°C
7. Storage Temperature: Tsg = -55 ~ +150°C