METHOD AND CIRCUIT FOR CONTROLLING CURRENT IN A HIGH PRESSURE DISCHARGE LAMP

摘要

A circuit for controlling current during run-up of a high pressure discharge lamp comprises a buck converter for generating a buck current to drive the high pressure discharge lamp and a control circuit coupled to the buck converter for varying the duty cycle of the buck current during run-up is disclosed. A method for controlling current in an electronic ballast during run-up of a high pressure discharge lamp comprises steps of detecting lamp ignition, providing a buck current to drive the lamp, and varying the duty cycle of the buck current during run-up to control the current in the lamp is also disclosed.