a. Redraw the above circuit using thermal noise current source.

b. Write the expression for total output thermal noise voltage.

c. Write the expression for output thermal noise voltage referred to the gate of MI.

d. Why should gm, be maximized and gm 2 be minimized in the above circuit?

Solution:

a) circuit using thermal noise current:

Representing the thermal noise of $M_1$ and $M_2$ by current sources and noting that they are uncorrelated we write.

$ V_{n, 0 u t}^2=4 \mathrm{KT}\left(r g m_1+g m_2\right)\left(r_0 111 r_2\right)^2 $

Since the voltage gain is equal to $g m_1\left(\mathrm{rO}_1 11\left(\mathrm{YO}_2\right)\right.$, the total …