16.6. Graphical Methodology for Analysis

Try these first

1. 1.

   What is the purpose of the saturation region in a MOSFET?

   Hint

   Think about how the MOSFET behaves when it is fully 'on'.

2. 2.

   Define the term Vgs.

   Hint

   Consider how this voltage affects the transistor's operation.

3. 3.

   What region indicates a MOSFET is fully 'on'?

   • Cut-off
   • Triode
   • Saturation

   Hint

   Think about how we define 'on'.

4. 4.

   True or False: The input current to a MOSFET is ideally zero.

   • True
   • False

   Hint

   Consider the implications of high impedance.

5. 5.

   If a circuit has a MOSFET with V_DD = 12V, R_D = 2kΩ, and the MOSFET has a transconductance parameter K = 0.3 mA/V² and V_th = 1.5V, calculate the output voltage when Vgs = 5V.

   Hint

   Break the problem into steps: Find current first, then use it to find voltage.

6. 6.

   Analyze a simple MOSFET amplifier circuit where the input signal causes the Vgs to vary. Discuss how variations affect the class of amplifier operation and performance.

   Hint

   Think about the conditions leading to saturation and cut-off in response to input changes.