A photodiode in an optical transmission system, such as shown in Figure 1.40, can be modeled as a Norton equivalent circuit with \(i_{s}\) in parallel with \(R_{S}\) as shown in Figure P6.67. Assume that the current source is given by \(i_{s}=2.5 \sin \omega t \mu \mathrm{A}\) and \(R_{S}=50 \mathrm{k} \Omega\). Design the common-base circuit of Figure P6.67 such that the output voltage is \(v_{o}=5 \sin \omega t \mathrm{mV}\). Assume transistor parameters of \(\beta=120\) and \(V_{A}=\infty\). Let \(V_{C C}=5 \mathrm{~V}\).

Figure 1.40:-

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Input signal Drive circuit Transmitter Receiver Photodiode LED Optical fiber Output Amplifier signal Figure 1.40 Basic elements in an optical transmission system