Half Wave and Full Wave Precision Rectifier Circuit using Op-Amp

When dealing with very low voltage AC signals in electronics, standard silicon diodes fall short because they require approximately 0.7 volts to conduct, effectively clipping or distorting tiny waveforms. To overcome this limitation, this project uses an LM358 operational amplifier integrated circuit combined with 1N4148 diodes, precision 6.8K resistors, and 1K resistors. By placing the diode inside the feedback loop of the op-amp, the circuit creates a 'super diode' or precision rectifier. The high open-loop gain of the op-amp compensates for the diode's forward voltage drop, forcing the output to accurately reflect the input signal even for voltages well below 0.7V. Powered by a dual ±10V power supply on a standard breadboard, the setup allows you to build both half-wave and full-wave rectification stages using the jumper wires to route signals between the two op-amp sections. The half-wave configuration passes only one polarity of the incoming waveform while eliminating the diode drop error, whereas the full-wave configuration combines inverted and non-inverted paths using the precision 1N4148 diodes and 6.8K resistors to invert the negative half-cycles, resulting in a continuous, uninterrupted positive output for any AC input.