The following is a multistage amplifier. It consists of 3 parts:
- Waveform generator and inverting amplifier
- A small signal amplifier with gain 20 and a small signal amplifier with gain 10
- A power amplifier where efficiency = 0.6 * maximum efficiency
When I do not connect the power amplifier, the output waveform on the second small signal amplifier is as expected, that is, 10 V. But, when I connect the power amplifier to its output, the output waveform on the second small signal amplifier decreases to mV. Why is it so? How can I correct it?