10 V
4k
4k
$V_{O1}$
$V_{O2}$
+ 8k
$V_{id}/2$ o
$Q_1$
$Q_2$
o -$V_{id}/2$
4k
$Q_3$
6k
2.65k
- 10 V
Q.1: Assume $\beta = \infty$ (Ignore base current)
\begin{itemize}
\item Find all the DC currents, voltages, and $I_{DC}$
\item Draw small-signal and find $|A_{vd}| = \frac{|V_{o1} - V_{o2}|}{|V_{id}|}$
\item Find $V_{CM}^{Max}$, $V_{CM}^{Min}$
\end{itemize}