3.1. Introduction to JFET

Try these first

1. 1.

   What does JFET stand for?

   Hint

   Think about the full form of JFET.

2. 2.

   Is a JFET a voltage-controlled or current-controlled device?

   Hint

   Remember how it regulates current flow.

3. 3.

   What type of device is a JFET?

   • Current-controlled
   • Voltage-controlled
   • Magnet-controlled

   Hint

   Think about what governs the flow in JFET.

4. 4.

   The cut-off voltage of JFET refers to what?

   • True
   • False

   Hint

   Recall what happens when the voltage reaches this threshold.

5. 5.

   If a JFET has a maximum drain current of 10 mA at VGS=0V and the cut-off voltage is -3V, what will be the drain current at VGS=-1.5V?

   Hint

   Substitute your known values carefully into Shockley’s equation.

6. 6.

   Describe the significance of controlling current by gate voltage in practical applications. How does this feature benefit electronic designs?

   Hint

   Consider the impact on efficiency in circuits.