Power transistors are finding increasing popularity in low to medium power applications.A power transistor has low current gain and requires continuous base drive during on-state conditions but doesn't require forced commutations.Circuitry power transistors can be used in high switching frequency,permitting size reduction of electromagnetic components and can provide current limit protection by base drive circuit.Power transistor cannot withstand reverse voltage and application is limited to dc voltage for inverters and choppers.
Transistor with high voltage and current ratings are known as power transistors.The current gain of power transistors(IC/IB)can be as low as 10.For eg. base current of 10A is required for 100A of collector current.
The V-I characteristics(output characteristics of power npn transistor is shown in figure below
Nombre: Lenny Ramirez
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