Question 10.7: Determining the Transresistance-Amplifier Model Find the tra...

Open circuit the output terminals, and analyze the circuit to determine R_{moc} .

With an open-circuit load, the output voltage is

v_{o\text{oc}}=A_{\text{voc}}v_i

and the input current is

i_i=\frac{v_i}{R_i}

Thus, we find the transresistance gain as

R_{\text{moc}}=\frac{v_{o\text{oc}}}{i_i} =A_{\text{voc}}R_i=100 \text{ k}\Omega

The resulting transresistance model of the amplifier is shown in Figure 10.17.