This is one of the transistor types.
Part Number: D1557, 3DD1557
Function: Low frequency amplification bipolar transistor
Package: TO-3P(H)IS Type
Manufacturer: Jilin Sino-Microelectronics
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Description
The D1557 is a high back pressure NPN bipolar power transistor, manufacturing The main technology employed: high-pressure technology mesa, triplet Diffusion of technology, the use of plastic full encapsulation structure.
Features
1. High voltage: VCBO = 1700V
2. Saturation pressure drop: VCE (sat) = 1V (max.)
3. High switching speed: tf = 0.8μS (max.)
4. High reliability
5. Environmental protection (RoHS) products
Applications: Color TV line output circuit
Pinouts:
Absolute maximum ratings
1. Collector-Base Voltage: Vcbo = 1700 V
2. Collector-Emitter Voltage: Vceo = 830 V
3. Emitter-Base Voltage: Vebo = 8 V
4. Collector Current: Ic = 10 A
5. Base Current : Ib = 5 A
6. Power Dissipation : Pc = 50 W
Reference Site:
http://monitor.espec.ws/section27/topic78212.html
D1557 Datasheet
