shown in figure $V_{BE}=0.7V, β=100, V_A=∞$

Mumbai University > EXTC > Sem 3 > Analog Electronics 1

Marks: 10 M

Year: Nov 2013

1. For DC equivalent circuit Capacitors are open circuited hence $R_S$ and $R_L$ are not part of DC circuit as shown in Fig2.

Fig1 DC equivalent circuit of amplifier

• Applying KVL to emitter base- loop

  $-I_BR_B-V_{BE}-I_ER_E+V_{EE}=0$

  $V_{EE}- V_{BE}= I_BR_B - I_ER_E$

  $V_{EE}-V_{BE}= I_BR_B+ (β +1)I_BR_E$

  $I_B=\frac{V_{EE}-V_{BE}}{R_B+(β +1)R_E}$

  $I_B={20-0.7}{100k+(101×2k)}$

  $I_B={19.3}{302k}$

  $I_B=63.9µA$ …