Start-up circuit for providing a start-up voltage to an application circuit

摘要

A startup circuit for providing a startup voltage from a high voltage DC bus voltage to an application circuit including an integrated circuit package for at least a control circuit for driving at least one power switch of the application circuit; a dropping resistor in the integrated circuit package having a first terminal for coupling to the high voltage DC bus and for dropping the high voltage DC bus voltage to a reduced voltage level at a second terminal; and a low voltage regulator in the package coupled to the second terminal for providing a startup regulated low voltage DC output at a preset level for powering at least one part of the application circuit during startup of the application circuit. The application circuit may be, for example, a switching mode power supply.