Cuestion 5 (Amplificacion, G en decibelios)

Image 2006Sept2C5
Solucion:

\begin{displaymath}R_{o}=100\,\Omega\end{displaymath}


\begin{displaymath}A_{vo}=2000\end{displaymath}


\begin{displaymath}R_{i}=2\,k\Omega\end{displaymath}


\begin{displaymath}R_{L}=300\,\Omega\end{displaymath}




\begin{displaymath}G=A_{v}^2\frac{R_{i}}{R_{L}}\end{displaymath}


\begin{displaymath}A_{v}=A_{vo}\,frac{R_{L}}{R_{o}+R_{L}}=2000\,frac{300}{100+300}=1500\end{displaymath}


\begin{displaymath}G=A_{v}^2\,\frac{R_{i}}{R_{L}}=15\,10^6\end{displaymath}




\begin{displaymath}G_{dB}=10\,log(G)=71.76\,dB\approx 71.8 \,dB\end{displaymath}



La respuesta correcta es la a).