19.2. Numerical Example

Try these first

1. 1.

   Define transconductance in the context of BJTs.

   Hint

   Focus on how input voltage affects output current.

2. 2.

   What does the small signal equivalent circuit simplify?

   Hint

   Think about the benefits of linear modeling in circuit analysis.

3. 3.

   What does transconductance represent in a BJT?

   • Resistance to current
   • Change in collector current per change in base-emitter voltage
   • Static current behavior

   Hint

   Think about how input affects output in BJTs.

4. 4.

   True or False: The output conductance defines a constant relationship between collector current and collector-emitter voltage.

   • True
   • False

   Hint

   Reflect on how varying conditions may influence circuit behaviors.

5. 5.

   A BJT circuit has a collector current of 5mA and a β of 250. How would you expect the output conductance to behave if the collector-emitter voltage is increased? Provide the explanation as well!

   Hint

   Reflect on how voltage can alter current pathways in BJTs.

6. 6.

   Given a BJT circuit with defined values, illustrate how you would derive the small signal voltage gain formula considering g_m, R_C, and load resistances in your approach.

   Hint

   Use relationships derived in class and apply them to the new components.