19.1.5. Current Gain Variation

Try these first

1. 1.

   What is transconductance?

   Hint

   Think about the current flow changes in relation to the input voltage.

2. 2.

   Define the output conductance.

   Hint

   Consider how current responds to voltage changes.

3. 3.

   What does transconductance measure?

   • Ratio of Output Current to Input Voltage
   • Change in Collector Current with change in Base Voltage
   • The slope of output current characteristic

   Hint

   Look for the relationship between collector current and the input voltage.

4. 4.

   True or False: Output conductance affects linearity.

   • True
   • False

   Hint

   Think about how circuit performance is influenced by these parameters.

5. 5.

   Given the small signal model parameters of a BJT with g_m = 3 mS and r_pi = 2 kΩ, calculate the output voltage gain if the load resistance is 1 kΩ.

   Hint

   Remember to calculate the parallel resistance first.

6. 6.

   A BJT amplifier exhibits a transconductance of 5 mS at an operating point of 10V and 20 µA. How does altering the operating point to 15V affect the transconductance if all other factors remain constant?

   Hint

   Consult the I-V characteristics of the BJT to evaluate changes.