A CE transistor is to be used in the amplifier of Fig. 3.72 with a source resistance

Question:

A CE transistor is to be used in the amplifier of Fig. 3.72 with a source resistance R_Sand collector resistor R_C. First, find the overall small-signal gain v_o/v_ias a function of R_S, R_C, Î²₀, V_A, and the collector current I_C. Next, determine the value of dc collector bias current I_Cthat maximizes the small-signal voltage gain. Explain qualitatively why the gain falls at very high and very low collector currents. Do not neglect r_oin this problem. What is the voltage gain at the optimum I_C? Assume that r_b= 0.

Figure 3.72

Vcc RC Vo Rs Vi