32.1.7. Small Signal Analysis

Try these first

1. 1.

   What is the function of the common source amplifier?

   Hint

   Think about what an amplifier does.

2. 2.

   Why do we use DC biasing in MOSFETs?

   Hint

   Consider the role of biasing.

3. 3.

   What is the main function of a common source amplifier?

   • Current amplification
   • Voltage amplification
   • Power amplification

   Hint

   Consider what is commonly amplified in analog circuits.

4. 4.

   True or False: AC signals affect the DC bias in a common source amplifier circuit.

   • True
   • False

   Hint

   Review the role of biasing.

5. 5.

   A common source amplifier has a transconductance of 1.5mS and is biased at 2V. For an input signal of 4V, find the output current when the threshold voltage is 1.5V.

   Hint

   Use the small signal current equation discussed.

6. 6.

   Design a common source amplifier circuit using an N-channel MOSFET to achieve a voltage gain of 10 while ensuring the MOSFET operates in the saturation region. Specify appropriate values for resistances.

   Hint

   Consider the resistor values that could yield a gain of 10 while respecting DC bias calculations.