Hello,
I have a 16V single supply amplifier design, the output of which is clipping at +/- around 1.5V.
When I disconnect the output stage, and view the waveform at the emitter of Q11, there is a clear waveform of about 5V peak-to-peak, with just a bit of expected non linear distortion, but as soon as I load it with the output stage I get the red waveform visible on the lower oscilloscope screen, and the output from emitter follower Q11 is clipped at -2V, visible as the blue waveform on the upper osc screen.
I have measured the DC bias around the circuit and it is consistently around 8V. There is a clear signal of about 20mV going into the base of common emitter Q9, which is biased at around 2.5V, and I have a quiescent current of around 1mA through the diodes.
I was wondering if anyone might be able to tell me why this is happening? What am I doing wrong in the output stage?
If you need any more info please let me know.
Thanks for looking!
I have a 16V single supply amplifier design, the output of which is clipping at +/- around 1.5V.
When I disconnect the output stage, and view the waveform at the emitter of Q11, there is a clear waveform of about 5V peak-to-peak, with just a bit of expected non linear distortion, but as soon as I load it with the output stage I get the red waveform visible on the lower oscilloscope screen, and the output from emitter follower Q11 is clipped at -2V, visible as the blue waveform on the upper osc screen.
I have measured the DC bias around the circuit and it is consistently around 8V. There is a clear signal of about 20mV going into the base of common emitter Q9, which is biased at around 2.5V, and I have a quiescent current of around 1mA through the diodes.
I was wondering if anyone might be able to tell me why this is happening? What am I doing wrong in the output stage?
If you need any more info please let me know.
Thanks for looking!
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