ECE3050 Homework Set 10The figures sho w a common-source amplifier, a common-drain amplifier, and a common-gate am-plifier. For each circuit, it is given that Rtg=1kΩ, Rts= 100 Ω,andRtd=10kΩ. The transistorshav e the parameters ID=1.5mA, VDS=10V, K =0.005 A/ V2,andλ =0V−1.1. For each transistor, show that gm=1/182.6S, rs= 182.6 Ω,andr0= ∞ kΩ.2. For the common-source amplifier of Figure (a):(a) Replace the MOSFET with the T model or simplified T model and show thatvo= −i0dRtd= −104i0di0d= i0s=vtgrs+ Rts=vtg282.6vovtg=−Rtdrs+ Rts= −35.4(b) Replace the MOSFET with the π model and show thatvo= −i0dRtd= −104i0di0d=vtg1gm+ Rts=vtg282.6vovtg=−Rtd1gm+ Rts= −35.43. For the common-drain amplifier of Figure (b):(a) Use the T model or simplified T model to show thatvovtg=Rtsrs+ Rts=0.354rout= Rtskrs=64.61 Ω1(b) Use the π model to show thatvovtg=Rts1gm+ Rts=0.354rout= Rtsk1gm=64.61 Ω4. For the common-gate amplifier of Figure (c)(a) Use the T model or simplified T model to show thatvovts=−1rs+ Rts× (−Rtd)=Rtdrs+ Rts=35.4rout= Rtd=10kΩ(b) Use the π model to show thatvovts=−11gm+ Rts× (−Rtd)=Rtd1gm+ Rts=35.4rout= Rtd=10kΩ5. What are the new answers to problems 4 through 6 if the body lead connects to ac groundand χ =0.3? Answers: For problem 2, vo/vtg= −32.0 and rout=10kΩ.Forproblem3,vo/vtg=0.32 and rout=58.4 Ω. For problem 4, vo/vts=32and
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