An n-channel MOSFET is biased in the saturation region at a constant VGS. (a) The drain current is ID = 0.250 mA at VDS = 1.5 V and ID = 0.258 mA at VDS = 3.3 V. Determine the value of λ and ro. (b) Using the results of part (a), determine ID at VDS = 5 V.
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An n-channel MOSFET is biased in the saturation region at a constant VGS. (a) The drain current is ID = 0.250 mA at VDS = 1.5 V and ID = 0.258 mA at VDS = 3.3 V. Determine the value of λ and ro. (b) Using the results of part (a), determine ID at VDS = 5 V.
![Question 2 The following parameters have been defined for the MOSFET amplifier circuit shown in Figure 2.1: VDD = 20 V, R1 = 2.2 MΩ, R2 = 1.8 MΩ, RD = 1.5 kΩ. (a) Given that the MOSFET has the parameters K = 0.475 mA/V2 and a turn-on voltage, Vto = 2.1 V, calculate the value of source resistance, Rs, needed to set a DC bias drain current of ID = 4 mA. [6 marks] (b) With Rs set at the value calculated in part (a), determine the value of the drain voltage, VD, and confirm whether or not the MOSFET is operating in the saturation region. [5 marks] (c) If the MOSFET has rd = 10 kΩ, complete the small-signal equivalent model for the amplifier circuit and calculate its input resistance, output resistance, open-circuit gain (i.e., with RL = ∞) and overall gain (when RL = 1 kΩ). [9 marks] Figure 2.1](https://www.doubtrix.com/uploads/editor/2185749880UDRAjiUDlM.png)