I have got a doubt about this circuit. to work this properly, the second stage should also have unity gain. how is this possible as for non inverting configuration, gain=1+Rf/R1?
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I have got a doubt about this circuit. to work this properly, the second stage should also have unity gain. how is this possible as for non inverting configuration, gain=1+Rf/R1?
It works fine. It's not real easy to understand how it works when Vi < 0. See attachment.You might be interested in some rectifier circuits. Yours is not properly set up - http://sound.westhost.com/appnotes/an001.htm
because we need a symmetrical waveform at the output. if the -ve half cycle of the i/p wave is amplified more by the equation 1+(Rf/R1), how can we get a symmetrical waveform? the above situation occurs when -ve half cycle gets inverted by 1st opamp and then passed by lower diode and then amplified by 2nd opamp. my question is what is the eqn for the gain in this 2nd stage? whether it is 1+(Rf/R1)?Why is the gain so important when its feature is to rectify?
Thanks for the explanation.See attachment.
The gain of the second stage depends on whether the input is positive or negative.because we need a symmetrical waveform at the output. if the -ve half cycle of the i/p wave is amplified more by the equation 1+(Rf/R1), how can we get a symmetrical waveform? the above situation occurs when -ve half cycle gets inverted by 1st opamp and then passed by lower diode and then amplified by 2nd opamp. my question is what is the eqn for the gain in this 2nd stage? whether it is 1+(Rf/R1)?
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