Figure 1 shows a 45 nm nMOS transistor. Assume Wn = 1 um and L = 45 nm. Assume the body of the transistor is connected to ground, VB = 0 V. a) Assume VD = VG = 1 V. Calculate the following; 1) Drain current, ID 2) Small-signal parameters, gm and gds 3) On-voltage (overdrive voltage), VON b) Assume VD = 0.1 V and VG = 0.6 V. Calculate the drain current, ID c) Calculate CGS, CGD, and CDB for VD = VG = 1 V. Assume that body (substrate) of the transistor is grounded.
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Figure 1 shows a 45 nm nMOS transistor. Assume Wn = 1 um and L = 45 nm. Assume the body of the transistor is connected to ground, VB = 0 V. a) Assume VD = VG = 1 V. Calculate the following; 1) Drain current, ID 2) Small-signal parameters, gm and gds 3) On-voltage (overdrive voltage), VON b) Assume VD = 0.1 V and VG = 0.6 V. Calculate the drain current, ID c) Calculate CGS, CGD, and CDB for VD = VG = 1 V. Assume that body (substrate) of the transistor is grounded.
![Problem 2.1: The N-channel enhancement type MOSFET in the following circuit has kn′ = 200 μA/V2, W/L = 20 /0.18, Vt = 0.6 V and λ = 0.1 V−1. Find the mode of its operation and the drain current in the following cases: (i) VG = 1 V and VD = 0.2 V and (ii) VG = 1 V and VD = 2 V. Key formulae: Cut-off condition VGS < Vt; current ID = 0 Linear region conditions VGS > Vt and VGD > Vt; current ID = kn′WL[(VGS − Vt)VDS − 12 VDS2] Saturation conditions VGS > Vt and VGD < Vt; current ID = 12 kn′WL(VGS − Vt)2(1 + λVDS) Solution: Case (i) VGS = and VGD = hence the mode of operation is ID = Problem 2.2: What is the mode of operation of the transistor in each of the following circuits? Take Vt = −0.8 V Note: Identify the type of the MOSFET transistor and take into account the change of the sign for all the voltages when you check the conditions for cut-off, linear mode and saturation. Solution:](https://www.doubtrix.com/uploads/editor/3781793919UXzwBdzxXp.png)