摘要 |
A ballast having a rapid inverter frequency control circuit that is used for programmed operation during lamps starting, during normal operation of all lamps and during no lamp(s) operation. A method and circuit controls frequency shift via a combination of different feedback circuits. A control signal for the inverter controller is synthesized as a sum of phase shifted inverter output voltage feedback signal and lamp current sense signal indicating status of each lamp connected to the ballast output. |