Use the following parameters for the circuit analysis: Vt = 1 V, k_n\'(W/L)=2mA/
ID: 2082487 • Letter: U
Question
Use the following parameters for the circuit analysis: Vt = 1 V, k_n'(W/L)=2mA/V^2, and lambda = 0. Assume all transistors are in saturation, and V_sig is an AC source. Transistor 1 has the following DC values: V_GS=1.5V, I_D=0.25mA Transistor 2 has the following DC values: V_GS=13.5V, I_D=156.25mA For the following hybrid-pi small-signal equivalent circuit, find the following values: (a) Rin (input resistance specified in the schematic) (b) Rout (output resistance specified in the schematic) (c) Overall voltage gain: V_o/V_rig.Explanation / Answer
To find the input resistance Rin, Short circuit the voltage source Vgs1 and open circuit the input current source.
So Rin=3K+30K
=33K ohm
To find the input resistance Rout, Short circuit the voltage source Vgs2 and open circuit the output current source.
So Rout=parallel combination of 20K and 2K
=(20*2)/(20+2)
=40/22
=1.812K ohm
(c) Overall voltage Gain=Vout/Vin
Where Vout=I*RL=(-Vgm2Vgs2/2)*(20000)