Exercise 3.11 Biasing in a radio receiver circuit


An answer:

IC = βfe βfe + 1IE IE = V E R6 V E = V B V BE V B = V CC R4 + R5 R3 + R4 + R5 IB (R4 + R5) R3 R3 + R4 + R5 IC = βfe βfe + 1 V CC R4+R5 R3+R4+R5 0.6V R6 + 1 βfe+1 (R4+R5)R3 R3+R4+R5

In this question, letting βfe from the start:

IC = IE IE = V E R6 V E = V B V BE V B = V CC R4 + R5 R3 + R4 + R5 IC = V CC R4+R5 R3+R4+R5 0.6V R6