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What should be the value of the current source Iᵢ so that the PMOS transistor is operating in saturation with VₛG = VₛD = 1 V? Vₛₛ = 2.5 V, |Vₜ| = 0.5 V, kᵖ = 4 mA/V². Neglect the channel-length modulation (that is, λ = 0).

User Edorian
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Final answer:

The PMOS transistor will be in saturation if the current source Ii is set to 1 mA, given the conditions VSG = VSD = 1 V, VSS = 2.5 V, |VT| = 0.5 V, and k^p = 4 mA/V^2.

Step-by-step explanation:

To find the value of the current source Ii that ensures the PMOS transistor is operating in saturation, we need to know the conditions for a PMOS device to be in the saturation region. A PMOS transistor is in saturation when VSG > |VT| and VSD ≥ VSG - |VT|. Given that VSG = VSD = 1 V, VSS = 2.5 V, and |VT| = 0.5 V with a transconductance parameter kp = 4 mA/V2, we first verify that both conditions for saturation are met.

VSG > |VT| is true as 1 V > 0.5 V. For VSD, since 1 V ≥ (1 V - 0.5 V), the second condition is also satisfied. Now we can use the saturation current equation for a PMOS transistor:

ID = kp(VSG - |VT|)2. Substituting the given values:

ID = 4 mA/V2 x (1 V - 0.5 V)2 = 4 mA/V2 x (0.5 V)2 = 1 mA

Therefore, the current source Ii should be set to 1 mA to ensure the PMOS transistor remains in saturation with the given parameters.

User Worldterminator
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