4.6. MOSFET Equations

Try these first

1. 1.

   What is the equation for the drain current in the saturation region?

   Hint

   Think about the relation to gate-source voltage and threshold voltage.

2. 2.

   Define threshold voltage.

   Hint

   Consider the conditions for conduction.

3. 3.

   What does VGS stand for?

   • Voltage-Gate Source
   • Voltage-Source Gate
   • Gate-Source Voltage

   Hint

   Look for how it relates to turning on the MOSFET.

4. 4.

   Is the threshold voltage required for a MOSFET to conduct?

   • True
   • False

   Hint

   Think about the minimum condition for operation.

5. 5.

   Design a MOSFET circuit where VGS should be adjustable and ID needs to be maximized; what parameters would you consider?

   Hint

   Reflect on how each of these could affect ID based on the equation.

6. 6.

   Create a situation where reducing VGS on an enhancement-mode MOSFET affects its performance in a switching circuit. What would you observe?

   Hint

   Think about the relationship between VGS, Vth and ID.