Chegg Solutions for Microelectronic Circuits (Adel S Sedra, Kenneth C Smith) (Z-Library)_parte_1532

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Step of 6 13.060P Refer to Figure 12.13 in the text book. The second or intermediate stage of the 741 operational amplifier is composed of and and the two resistors and R, Transistor acts as an emitter follower, thus giving the second stage a high input resistance. This minimizes the loading on the input stage and avoids loss of gain. Transistor acts as a common-emitter amplifier with a 100 Ω resistor in the emitter. Its load is composed of high output resistance of the current source in parallel with the input resistance of the output stage. The variation on the design of the 741 second stage is, = Find the ac emitter resistance of transistor Q16 Substitute 16.2 for and 25 mV for 25 mV 16.2 1.54 Step of 6 Find the ac emitter resistance, The collector current flowing through the transistor is, Substitute 550 for and 25 mV for 25 mV 550 Determine the resistance Substitute for 200 for and 50 Ω for =(200+1)(45.45+50) Step of 6 The input resistance of the second stage of the 741 operational amplifier is, = Substitute for for R, for and 200 for = =(201)[1.54x10'+13.873x10 Step of 6 The resistance R, IS Determine the resistance = The base voltage at the transistor is, = = V Determine a 200-1 = 200+1 =0.99 Step of 6 The current through the transistor is. A Step of 6 Thus the transconductance is, =9.335 A/V Thus the parameters corresponding to the variation in the design of the 741 second stage are