32.1.6. Circuit Description

Try these first

1. 1.

   What is the main role of biasing in a common source amplifier?

   Hint

   Think about how a BJT operates.

2. 2.

   Why is the source terminal termed 'common' in a common source amplifier?

   Hint

   Consider the structure of the circuit.

3. 3.

   What is a common source amplifier primarily used for?

   • Voltage gain
   • Current gain
   • Power gain

   Hint

   Recall the main function of amplifiers.

4. 4.

   True or False: The gate current in a MOSFET common source amplifier is zero.

   • True
   • False

   Hint

   Think about how a MOSFET is designed.

5. 5.

   A common source amplifier has a transconductance of 2 mS. If the biasing voltage is set at 3V and the threshold voltage is 1.5V, calculate the output current when the input signal voltage is 0.5V.

   Hint

   Always plug the numbers into the transconductance equation.

6. 6.

   Design a common source amplifier circuit for a specific application requiring a gain of 10 with a load resistor of 1kΩ. What value of the drain resistor should be used?

   Hint

   Think about the relationship between resistance and gain in your design.