Patent ID: 7388335
Filing Date: 2008-06-17
Classification: H05B,Y02B

Abstract:
1. An apparatus for providing a sinusoidally amplitude-modulated operating voltage, in particular for feeding a half-bridge inverter ( 10 ) having a high-pressure discharge lamp coupled thereto, having two switches (QHIGH and QLOW) arranged in the form of a half bridge, of which a first switch (QHIGH) is driven by a first signal in a clocking with the amplitude modulation frequency per clock cycle and a second switch (QLOW) is driven by a second signal, which is shorter than the first signal, with a temporal offset with respect to the first signal in each clock cycle, and having an LC element (LMOD, CMOD), which is arranged downstream of the half bridge, acts as a filter for the signal resulting from the driving of the switches at a connection point (K) between the switches, allows a DC voltage component and a sinusoidal component of the signal with the fundamental frequency of the clocking to pass through and substantially filters out harmonics.