18.1.7. Small Signal Transfer Characteristic

Try these first

1. 1.

   What is the purpose of linearization in circuit analysis?

   Hint

   Think about why engineers would want to simplify complex calculations.

2. 2.

   Define the term Q-point.

   Hint

   Recall the context in which you usually refer to the Q-point.

3. 3.

   What does linearization provide when analyzing a non-linear circuit?

   • It makes the circuit simpler
   • It eliminates the need for calculations
   • It provides a non-linear model

   Hint

   Think about why we would want simpler calculations.

4. 4.

   True or False: The operating point is the same as the maximum current in a circuit.

   • True
   • False

   Hint

   Focus on what the operating point actually signifies.

5. 5.

   A BJT operates with a collector voltage of 5V and a base voltage that varies with a small signal of ±0.2V. Analyze this system using your knowledge of small signal analysis. How would you define the Q-point and linearize around it?

   Hint

   Identify the DC conditions carefully and remember to use derivatives for linearization.

6. 6.

   If a small signal causes a change in the collector current to be approximately -20mA/V at the operating point, calculate the output voltage swing when the input small signal varies ±0.1V.

   Hint

   Apply the relationship between input, output, and small signal parameters accurately.