Question

Find the operating region of N-channel MOSFET with VGS = 1.4V, VTN = 0.5V, VDS = 1.8V

• A. Linear
• B. Cut-off
• C. Triode
• D. Saturation

Hint:

The operating region of MOSFET depends on two key parameters: the gate-source voltage (VGS) and drain-source voltage (VDS).

Answer 1

The Correct Option is D

Step 1: Determine if the MOSFET is ON. For the MOSFET to be ON, \(V_{GS}\) must be greater than the threshold voltage \(V_{TN}\). \[ V_{GS} = 1.4 V > V_{TN} = 0.5 V \] Since \( V_{GS} > V_{TN} \), the MOSFET is ON.
Step 2: Check if the MOSFET is in the saturation or the triode region. This is done by comparing \(V_{DS}\) and \(V_{GS} - V_{TN}\). \[ V_{GS} - V_{TN} = 1.4 - 0.5 = 0.9 V \] Since \( V_{DS} = 1.8V \) is greater than \( V_{GS} - V_{TN} = 0.9V \), the MOSFET is in the saturation region.