Acommercial wideband monolithic feedback amplifier (the 733) is shown in Fig. 8.51. This consists of a local series-feedback stage feeding a two-stage shunt-shunt feedback amplifier. The current output of the input stage acts as a current drive to the shunt-shunt output stage.

(a) Assuming all device areas are equal, calculate the collector bias current in each device.

(b) Calculate input impedance, output impedance, and overall gain υ_o/υ_i for this circuit at low frequencies with R_L = 2 kΩ. Also calculate the loop gain of the output stage.

Data: β = 100, r_b = 0, r_o = ˆž.

Fig. 8.51:

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