Patent ID: 8384292
Filing Date: 2013-02-26
Classification: H05B

Abstract:
1. A method of protecting a ballast from damage due to an inrush current using a microcontroller, the method comprising steps of: detecting a loss of input power received by the ballast; in response, entering the ballast into a standby mode, wherein the ballast is able to remain in the standby mode for a standby period of time; and monitoring the input power during the standby period of time to measure a start time, measurement of the start time being triggered by the ballast receiving input power again; and entering the ballast into an active mode when the measured start time exceeds a protection time, wherein the protection time corresponds to an amount of time needed for an inrush current to dissipate following input power again being received by the ballast, resulting in protection of the ballast from possible damage due to the inrush current; and allowing the circuit to turn on upon the ballast entering the active mode; and prohibiting a PFC circuit from turning on until the ballast is in the active mode; and wherein allowing comprises: allowing the PFC circuit to turn on upon the ballast entering the active mode.