In a power supply context, what does "pulsating DC" refer to?

Pulsating DC refers to a type of direct current that is not constant but varies in amplitude over time. This fluctuation occurs as the voltage level rises and falls periodically, typically as a result of the rectification process where AC (alternating current) is converted to DC. In this context, pulsating DC characterizes the output of a rectifier that has not yet undergone sufficient filtering to smooth out the variations, leading to a waveform that resembles the peaks of the input AC signal. This means the voltage level does not remain steady but shows pulsations rather than a smooth, continuous flow of current, which would be typical of pure DC. Understanding pulsating DC is essential in power supply design, as it impacts the performance and behavior of electronic circuits.