A simplified high-frequency equivalent circuit of a common-emitter amplifier is shown in Figure P7.82. The input signal is coupled into the amplifier through \(C_{C 1}\), the output signal is coupled to the load through \(C_{C 2}\), and the amplifier provides a midband gain of \(\left|A_{m}\right|\) and an upper \(3 \mathrm{~dB}\) frequency of \(f_{H}\). Compare this single-stage amplifier design to one in which three amplifier stages are used between the signal and load. In the three-stage amplifier, assume all parameters are the same, except \(g_{m}\) for each stage is one-third that of the single-stage amplifier. Compare the midband gains and the bandwidths.

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RS CC 1 CC2 ww HH +1 www HH RL RC\ 8mV Figure P7.82 Amplifier stage