This post explains for the transistor 2SD2646.

The Part Number is D2646.

The function of this semiconductor is 700V, NPN transistor.

The package : TO-3PMLH Type.

Manufacturer: Sanyo Semiconductor

Preview images :

Description

D2646 is 700V, 10A, NPN Triple Diffused Planar Silicon Transistor. 

 

Features:

• High speed.

• High breakdown voltage(VCBO=1500V).

• High reliability(Adoption of HVP process).

• Adoption of MBIT process.

 

 

Absolute maximum ratings ( Ta=25°C )

1. Collector to Base Voltage: Vcbo = 1500 V

2. Collector to Emitter Voltage: Vceo = 700 V

3. Emitter to Base Voltage: Vebo = 5 V

4. Collector Current: Ic = 10 A

5. Collector Dissipation : Pc = 3 W

6. Junction Temperature: Tj = 150°C

7. Storage Temperature: Tsg = -55 ~ +150°C

D2646 PDF Datasheet

This post explains for the transistor.

The Part Number is C3306, 2SC3306.

The function of this semiconductor is 400V, 10A, NPN Transistor.

Manufacturer: Toshiba Semiconductor

Preview images :

Description

C3306 is 400V, 10A, Silicon NPN Transistor. 

1. Forward Biased: In order to operate, the base-emitter junction of an NPN transistor must be forward biased, meaning that the base must be connected to a positive voltage relative to the emitter.

2. High Input Impedance: NPN transistors have a high input impedance, which means that they are less likely to draw current from the input source, and are therefore less likely to cause a drop in voltage across the source.

3. Inverted Output: NPN transistors are known for producing an inverted output relative to their input. That is, if the input signal is high, the output signal will be low, and vice versa. This behavior is due to the way the transistor is designed and is an important characteristic for many electronic applications.

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Absolute maximum ratings ( Ta=25°C )

1. Collector to Base Voltage: Vcbo = 500 V

2. Collector to Emitter Voltage: Vceo = 400 V

3. Emitter to Base Voltage: Vebo = 7 V

4. Collector Current: Ic = 10 A

5. Collector Dissipation : Pc = 100 W

6. Junction Temperature: Tj = 150°C

7. Storage Temperature: Tsg = -55 ~ +150°C

Applications:

1. Switching regulator

2. High voltage switching

3. High speed DC-DC converter

C3306 PDF Datasheet