2.2.2. PMOS Transistor Behavior

Try these first

1. 1.

   What happens when VGS is above Vth for a PMOS transistor?

   Hint

   Think about the threshold condition.

2. 2.

   What type of channel do PMOS transistors use?

   Hint

   Recall the type designation of the PMOS transistor.

3. 3.

   What is the threshold voltage for a PMOS transistor?

   • Positive
   • Zero
   • Negative

   Hint

   Think about how p-type devices operate.

4. 4.

   In which region does a PMOS transistor conduct current linearly?

   • True
   • False

   Hint

   Look back at the operation regions.

5. 5.

   A PMOS transistor is connected in a CMOS inverter, with a threshold voltage of -2V. If the gate-source voltage is -3V and VDS is sufficient to ensure saturation, what will be the state of the PMOS transistor?

   Hint

   Investigate the state of the PMOS concerning VGS and Vth.

6. 6.

   If a PMOS transistor's drain current is calculated using ID = 1/2 Kp (VSG - |Vth|)^2 (1 + λVDS), how would increasing VDS impact the current assuming λ is significant?

   Hint

   Focus on how the parameter λ interacts with VDS in the equation.