3 stage multi amplifier help!!

Thread Starter


Joined Jul 16, 2005
Can anyone give me some help on this. i need do hand in this assignment soon and i am have totally no idea how to solve it. .

Circuit diagram : http://imageshack.us/photo/my-images/198/circuit1x.jpg/

A multistage amplifier is shown in Fig. 9-1. You may assume that the body and the source
terminals of the NMOS and PMOS are connected together, i.e. no body effect for NMOS and
PMOS. You may also assume the following device parameters and all pnp BJT, NMOS and
PMOS devices are identical:
• β=100, VA=100, Cπ=4.9pF, Cμ=1.7pF
• Kn=2mA/V2, VTHN=1V, λn=0.001V-1 , Cgd=0.5pF, Cgs=5pF
• Kp=2mA/V2, |VTHP|=1V, λp=0.001V-1, Cgd=0.5pF, Cgs=5pF

1) Find out the small signal AC parameter for Q1A and M1A?
Obtain the expression for the small signal gain (vout/vs) of the amplifier. 2)AssumeRD1=RD2, design RD1 such that the small signal gain=100.
3) Estimate the Rin and Rout using RD1 and RD2 value in Question 1.


Joined Nov 25, 2009
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