19.2.1. Calculating Small Signal Parameters

Try these first

1. 1.

   What is transconductance?

   Hint

   Think about how the output responds to variations in the input voltage.

2. 2.

   How is base to emitter resistance computed?

   Hint

   Consider the circuit's behavior at the Q-point.

3. 3.

   What does transconductance measure in a BJT?

   • A. Collector current change
   • B. Base current change
   • C. Change in collector current over Vbe
   • D. Change in base-emitter voltage

   Hint

   Consider what parameters define the efficiency of signal amplification.

4. 4.

   True or False: The small signal equivalent circuit simplifies analysis by linearizing around the Q-point.

   • True
   • False

   Hint

   Think of how operating points stabilize circuit behavior.

5. 5.

   Calculate the transconductance for a BJT operating at a collector current of 2mA with a Vbe of 0.7V. Assume the thermal voltage is 25mV.

   Hint

   Make sure to use the correct values for your calculations.

6. 6.

   Discuss the implications of operating a BJT at maximum collector current and its effect on output conductance.

   Hint

   Think about how excess current alters behavior.