Precision Full Wave Rectifier

139

02:53:24

Returns the absolute value of the sinusoidal input signal

published 8 years ago

calvin21

8 years ago

Bonus: Change the resistor value and evaluate the effect on the gain of the positive- and negative halfcycles of the input sinusoid

IvanRiv

8 years ago

Question. What is the point of adding a second OpAmp? You can get the very same signal out of the first OpAmp (the cathode of the diode)

calvin21

8 years ago

Not quite. That would make it a Half Wave Rectifier (HWR). The second opamp ensures that the negative halfcycle is also carried through, but is inverted to the positive region.

calvin21

8 years ago

Negative halfcycle of the signal after it passes the inverting opamp, that is.

calvin21

8 years ago

The second opamp creates an alternative feedback path for the first opamp. I'll post a full explanation when I get time.

IvanRiv

8 years ago

Okay... I totally get it. But why does it work both in the simulation and physically? I made the circult in my school's lab and it works like a charm with one diode, one OpAmp and two resistors.

calvin21

8 years ago

Can you send me a link to your simulation?

IvanRiv

8 years ago

Sure: http://everycircuit.com/circuit/5028148407435264

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