Power supply with improved inrush circuit for limiting inrush current

摘要

A new and improved rectifier power supply operates in a low voltage mode of operation and a high voltage mode of operation without user intervention and includes an inrush current limiting device that is in circuit during a predetermined period of time during start up and bypassed during steady state operation in the low voltage mode of operation. In the high voltage mode of operation, when inrush current is reduced relative to the low voltage mode of operation, the inrush limiting device always remains in circuit. As there is no power loss associated with the inrush limiting device in the steady state low voltage mode of operation, the power supply has an improved efficiency and reliability and a reduced cost as it can be rated for continuous operation only in the high voltage mode of operation when the input current is lowest and device dissipation is least.