19.1.8. Application of Small Signal Equivalent Circuit

Try these first

1. 1.

   What is the purpose of small signal analysis?

   Hint

   Think about why we need to analyze complex circuits.

2. 2.

   Define transconductance.

   Hint

   It's a measure of how sensitive the collector current is to voltage changes.

3. 3.

   What does g_m represent in a BJT?

   • Base-emitter resistance
   • Transconductance
   • Output conductance

   Hint

   Think about how collector current behaves with voltage changes.

4. 4.

   True or False: The output conductance g_o shows how collector current varies with changes in input voltage.

   • True
   • False

   Hint

   Consider which voltage is being referenced in each context.

5. 5.

   Given a BJT with g_m = 15 mS, an R_C load of 2 kΩ, calculate the voltage gain and explain its significance.

   Hint

   Remember what a negative gain indicates in terms of phase.

6. 6.

   If a small signal input causes a current increase that exceeds predicted values due to Q-point shifts, discuss the implications on design choices.

   Hint

   Think about how variations can lead to misbehavior in amplifiers.