Patent ID: 7944151

Claim:
An electronic control gear (ECG) for a high intensity discharge (HID) lamp, comprising: a function generator that receives an input signal, wherein the input signal operates the lamp, wherein the function generator frequency modulates the input signal, generating a frequency modulated output signal that drives an arc of the lamp, wherein the frequency modulation of the input signal by the function generator sweeps continuously between a low frequency modulation and a high frequency modulation, the low frequency modulation being a frequency f 1 in a range of about 125 kHz to 150 kHz and the high frequency modulation being a frequency f 2 in a range of about 230 kHz to 300 kHz, where f 2 minus f 1 is at least 0.4 times f 1 ; and a variable gain transformer that adjusts a voltage of the frequency modulated output signal during starting of the lamp.