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Preamplifier with a class AB power amplifier

I am tasked on completing a power amplifier coupled by a pre amplifier to amplify a signal by a gain of 20.

The design must make use of a common emitter circuit such as the one in this url: https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.electronics-tutorials.ws%2Famplifier%2Famp...

The design must swing the output around zero and not draw more than 1.5mA from the input. also the voltage rails must be 20V and -20V. Any help on this would be greatly appreciated.
chrisfletcher
erik_squires
16,058 posts
 
DIYaudio is a great place to ask this question, but this sounds like homework that you should be reviewing your class notes. :)
atmasphere's avatar
atmasphere
11,803 posts
 
So- does the amp or the preamp need this gain stage? It can be used in both.

This circuit was used a lot in many early 1970s solid state power amps as the input voltage amplifier. Obviously this circuit does not need or use a bipolar power supply. Its also going to 'swing the output around zero' owing to the use of an output coupling capacitor.

If used as the input to a power amp, you only need three more transistors to make a solid state power amp that has the required gain.
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