Smoothing circuit

In a DC regulated power supply, the process of generating a stable DC voltage from commercial power begins by converting the input voltage into a unidirectional DC voltage, such as full-wave rectified current, using diodes in a rectifier circuit. However, at this stage, the output is a pulsating current and the voltage is not stable. Therefore, by removing the AC components contained in the pulsating current with a rectifier circuit, the output is averaged and stabilized. In other words, a smoothing circuit functions as a low-pass filter that removes low-frequency components contained in the pulsating current that have frequencies equal to integer multiples of the commercial power supply frequency.