Bridge Rectifier

A bridge rectifier is four diodes in one package that turn AC into DC. Whichever of its two AC terminals is higher, current leaves through the + terminal and returns through the − terminal, so the output keeps one polarity through both halves of the AC cycle (full-wave rectification). In DCACLab the part marks its AC, + and − terminals and shows which diodes are conducting; with a slow source the two pairs can be seen taking turns.