Discharge lamp e.g. metal halide lamp, supply circuit for motor vehicle headlight, has switching circuits whose triggering frequency is shifted in frequency region which is higher than resonance frequency of series resonance circuit

摘要

The circuit has a control section (6) which triggers switching circuits (5H,5L) so that the triggering frequency approaches a resonance frequency of a series resonant circuit. The trigger frequency is then continuously shifted from the frequency before switching-on the lamp to the frequency after switching-on the lamp in a frequency region which is higher than the resonance frequency when the lamp is switched on.