Im trying to understand how a super diode works. I understand that when the input is negative, the opamp output is positive, this forward biases the diode, and sends all of the current to the opamp output. What i dont understand is the simulation results i am seeing. It takes a while for the negative swing to be rectified. This happens regardless of frequency or input voltage. Does someone know why this is happening? I am using an ideal OpAmp in this simulation.
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Answered my own question as i looked deeper into it. From the text book:
The rectifier circuit shown above has the property that for positive inputs the operational amplifier output saturates in the negative direction.
– The op-amp output voltage is required to change instantaneously from this saturated voltage, (Vs-) to +0.6 V when the input waveform passes through zero.
– Because of the limited slew rate of real operational amplifiers this cannot occur, and the output waveform will not be a precisely rectified version of the input waveform as the frequency of the input sinusoid is increased.
Ill leave this here in case someone has the same question in the future.