Which component in power supplies rectifies AC to DC?

The rectifier is the component responsible for converting alternating current (AC) to direct current (DC) in power supplies. This is a critical function in power supply design, as many electronic devices operate exclusively on DC power.

Rectifiers typically use semiconductor devices, such as diodes, which allow current to flow in only one direction. During the positive half-cycle of the AC waveform, the rectifier conducts and allows current to pass, while during the negative half-cycle, it blocks the flow of current. This conversion process creates a pulsating DC signal, which usually needs further filtering and regulation to become stable DC power suitable for electronic applications.

In contrast, transformers adjust voltage levels but do not rectify, filters smooth out the output but do not convert AC to DC, and voltage regulators maintain stable voltage levels but also do not handle the rectification process. Each of these components serves a unique purpose in the power supply, but only the rectifier performs the essential function of transforming AC into DC.