In electrical terms, what is ‘ripple’?

Ripple refers to the small, unwanted AC voltage that is superimposed on the DC output. In power supply circuits, especially those that convert AC to DC, ripple is a consequence of the rectification process. During this process, the AC signal is transformed into a DC signal; however, the output is not a perfect flat line of DC voltage. Instead, residual AC components remain, which cause fluctuations or "ripples" around the DC level.

Managing ripple is crucial because excess ripple can lead to poor performance in electronic circuits, affecting the reliability and stability of the supply voltage that powers devices. Engineers often use filtering methods, such as capacitors and inductors, to reduce ripples to acceptable levels in the power supply design. This ensures that the output voltage is as smooth and steady as possible, minimizing interference and enhancing the performance of the electronic components it supplies.