申論題

3.(30%) The amplifier shown in Fig. 3 has =R_L = 1 kΩ, R_c= 1 kΩ, R_B = 47 kΩ. The BJT has 0.7 V, β= 100, Cμ = 0.8 pF, f_T = 600 MHz, and thermal voltage V_T = 25 mV. Assume the coupling capacitors to be very large. Neglect the Early effect. (a) Find the collector current of the transistor. (b) Find the overall gain vdvsig and the input resistance at midband frequency. (c) Find the high frequency response f_H. (5%,5%,10%,10%)