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The cascode current source shown below must be designed for a bias current of 0.5 mA. Assume Kn = 5 mA/V2 and Vth = 0.4 V for both M1 and M2. (a) Neglecting channel-length modulation, compute the required value of Vb2. What is the minimum tolerable value of Vb1 if M2 must remain in saturation? (b) Assuming lambda = 0.1 V-1, calculate the output impedance of the circuit.

The cascode current source shown below must be designed for a bias current of 0.5 mA. Assume Kn = 5 mA/V2 and Vth = 0.4 V for both M1 and M2. (a) Neglecting channel-length modulation, compute the required value of Vb2. What is the minimum tolerable value of Vb1 if M2 must remain in saturation? (b) Assuming lambda = 0.1 V-1, calculate the output impedance of the circuit.

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The cascode current source shown below must be designed for a bias current of 0.5 mA. Assume Kn = 5 mA/V2 and Vth = 0.4 V for both M1 and M2. (a) Neglecting channel-length modulation, compute the required value of Vb2. What is the minimum tolerable value of Vb1 if M2 must remain in saturation? (b) Assuming lambda = 0.1 V-1, calculate the output impedance of the circuit.

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