I
[email protected]
- Jan 1, 1970
- 0
I have some doubts about phase compensation.....
I'm reading Graeme book about transimpedance amplifiers with opamp:he
puts a zero of feedback function at frequency with 0dB loop gain. So,
supposed that 2 first poles (open loop gain of opamp and pole of
feedback loop) are totally evolved, he obtains a phase margin of 45°.
This is ok, but there is a frequency range where phase loop is 360°:
so i think oscillations are present. Why in stability analysis only
phase margin is considered and not the entire phase evolution?
Thanks in advance
I'm reading Graeme book about transimpedance amplifiers with opamp:he
puts a zero of feedback function at frequency with 0dB loop gain. So,
supposed that 2 first poles (open loop gain of opamp and pole of
feedback loop) are totally evolved, he obtains a phase margin of 45°.
This is ok, but there is a frequency range where phase loop is 360°:
so i think oscillations are present. Why in stability analysis only
phase margin is considered and not the entire phase evolution?
Thanks in advance