I'm trying to analyze the below circuit. It's a textbook problem (Malvino's Electronic Principles) and the answer is given in the back (8966), but I am unable to reach that answer or approximation.
The goal is to figure out what is the total voltage amplification of the below circuit:
The Op-Amp part is pretty easy, since it's simply a non-inverting amplifier with a feedback configuration, so the amplification is (47k/1k + 1 = 48).
For the transistor, I'm having a difficult time. Particularly, the 1k resistor is throwing me off. I think it's in series with the voltage divider biased circuit, so I am approaching the analysis like this:
\$I_E = (15(10/33)-0.7)(1/5600) = 36.4 mV\$ (assuming 1k, 22k, 10k resistors form a voltage divider)
\$r'_e = 25 mV/I_E = 36.4 ohm \$
\$r_c = 6800\$ assuming the input impedance of the 741c is very high
\$A = r_c / r'_e = 186.8 \$
Total Amplification = 186.8 * 48 = 8967 which gets me pretty close to the textbook's answer.
I don't know if my analysis is correct though. I tried to simulate the circuit in LTSpice, but I got a larger voltage drop across the 1k resistor than my analysis would suggest so I just wanted to see if anyone would approach differently.