Multi-path constant current driving circuit

Abstract

A multi-path constant current drive circuit includes a DC/AC converter, a main transformer and at least two rectifying and filtering units. The main transformer includes at least one assistant side winding with a tap; together with the assistant side winding of the main transformer, each of the at least two rectifying and filtering units respectively forms a power supply loop; each power supply loop includes a first rectifying loop and a second rectifying loop, which are relatively used for the rectification of the positive and the negative half-cycle alternating voltage; a current-equalizing transformer is arranged between the adjacent first power supply loop and second power supply loop, the windings of the current-equalizing transformer are respectively in the rectifying loops contained in the first power supply loop and the second power supply loop, thus realizing the current equalization between the different rectifying loops in which the adjacent rectifying and filtering units are contained. The multi-path constant current drive circuit performs a good current equalization, and can reduce the volume of the current-equalizing transformer and decrease the cost.