Summing Amplifier

Load the PSPICE file suma1.sch, shown in Figure 17.

**Figure 17:** Summing amplifier.
$\begin{figure} \begin{center} \epsfig{file=images/clab2img5.eps}\end{center}\end{figure}$

Show that the circuit performs the sum (with inversion):

$\begin{displaymath}V_{out} = - 4 v_{in\,a} - 2 v_{in\,b} \end{displaymath}$

(1)

Simulate the circuit and check (1) for various values of $V_{in\, a}$ and $V_{in\, b}$ .

If $V_{in\, b}=1$ V, what is the range of values of $V_{in\, a}$ for which the amplifier is not saturated?

ANU Engineering - ENGN2211