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Problem 1: This is a large signal problem

Electrical Engineering

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Problem 1: This is a large signal problem. Suppose the MOSFETs drawn have g„, = 1 mS when VGS = 2.5 V, and Vih = 0.5 V. 
yin 
VDD = 5 V 
Vont 
RL = co 
(a) Plot the load line analysis of the MOSFETs' IV characteristics when Vh, = 4 V. 
yin 
(b) Derive the complete equations to determine a given Vi„,Vo„t point for these two regions: 0.5 < VG s < 2.5, 2.5 < VGs < 4.5. Hint: in most cases, what modes are the MOSFETs in? 

Problem 2: 

This is a small-signal problem built up towards a transfer function. Suppose the MOSFETs drawn have gm = 1 mS when VGS = 2.5 V, and Vth = 0.5 V. 
Vtn Rs = 5 
VDD = 5 V 

Your 
Vow 
(a) Derive Av for this circuit assuming RL = co, draw the transfer function on the first plot above, and label Av. Explain whether you expect clipping or not. 
(b) Derive Av for this circuit assuming RL = 5011, draw the transfer function on the second plot above, and label Av. 
 

Problem 3: 

VC This is a Bode plot problem. 
R, Vi„ V„„, 

R2 > R1 
20 loglAv 
w 
(a) Derive Av for this RC circuit. Try to simplify it to where the numerator and denominator are polynomials of o. (b) Plot the Bode plot for Av. (c) Take the limits for Av under the following conditions: R1 0, R2 CO.