Hi, i''ve been given this task:
You are required to design a multi-stage audio amplifier with the following specification:
Voltage gain 250
Input resistance 200 kOhm
Output resistance 5 Ohm
Current drain 15 mA
Supply voltage 12 Volt
This must be done using discrete components. We have been ''taught'' common collector gain stages using NPN and PNP BJT transistors. We also can use a Darlington pair for impedance at the beginning of the circuit (using the emitter output so there is no gain). A capacitor to DC block is also on the input and the output of the example circuit that i have seen.