Subject: CMOS VLSI Design

Topic: Mixed Signal Circuits

Difficulty: Medium

i) Sampling mode: $S_1$ and $S_3$ -> ON and $S_2$ -> OFF , creating virtual ground at X and allowing voltage across $C_1$ to track iput voltage.

ii)Amplification mode: $S_2$ -> ON, injects a constant charge $\Delta q_2$ onto node X.

iii) Subsequently, $S_1$ turns OFF and $S_3$ turns ON,
$\therefore \,\,V_P$ goes from $V_{in}$ to 0.
output voltage changes from 0 to $V_{in_{0}}(\frac{C_1}{C_2})$
providing a $A_v$ of $\frac{C_1}{C_2}$.

iv) We call the circuit "non-inverter amplifier" because, final output has same polarity as $V_{in_{o}}$ and the gain can be greater than unity.

$C_{tot}$ at (X) = $(1+A)K_F$
$\therefore\,\, Pole\,\,\,freq=\frac{1}{R_S(1+A)C_F}$ rad/s .