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An IC 7840 regulator has an output current =180mA and internal resistor =10Ω. Find the collector current in the output using the transistor specification: ß=15 and VEB(ON) =1.5v.

An IC 7840 regulator has an output current =180mA and internal resistor =10Ω. Find the collector current in the output using the transistor specification: ß=15 and VEB(ON) =1.5v. Correct Answer 450mA

The collector current from transistor, IC= ßIB Where, IB= IO-(VEB(ON)/R1) = 180mA-(1.5v-10Ω) = 0.03A. Therefore, IC= 15×0.03 = 0.45A = 450mA.

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