Abstract: The invention relates to a circuit arrangement for operating electrical lamps which encompasses an invertor (WR) with oscillation build-up circuit (trigger generator), comprising diac (DC1) and drive circuit. The drive circuit comprises a high-pass filter, in particular an RC high-pass filter (R1, C1). As a result, the trigger initiation is shifted closer to the zero crossing of the supply voltage. This means, in turn, that a more sinusoidal power supply current consumption with a smaller proportion of harmonics is obtained. In addition, more stable lamp operation is achieved in combination with power supply segment control dimmers.

Abstract: The invention relates to optimized-loss base drive for a bipolar transistor bridge oscillator circuit, by using base series capacitors and by not hng any non-reactive resistances in the base drive circuits.

Abstract: A circuit is proposed for the AC voltage operation of a discharge lamp by ans of a coupling capacitor (C3) with a safety disconnection device, connected in series with the lamp for DC current separation, which is characterized by the fact that the safety disconnection device responds to a DC voltage (UC3) at coupling capacitor (C3) by means of a DC current component flowing through the lamp.

Abstract: A circuit is proposed for the high-frequency operation of at least one lamp with an active harmonic filter with at least one capacitive pump branch with a pump capacitor (C1; C2) for feeding the energy back to a filter capacitor (C4) from a connection point on the lamp side between and including a central tap of the push-pull frequency generator and a first lamp diode, is characterized by the fact that a trapezoidal capacitor (CT1; CT2) is provided between a point of at least one pump branch, which, from the central tap of the push-pull frequency generator, lies out behind capacitor (C1; C2) of the pump branch, and one of the external taps, and thus the one or more pump capacitors of the one or more pump branches are the only capacitors connected in a direct capacitive load at the central tap of the push-pull frequency generator and/or no resonance capacitor (C6) connected directly in parallel to the lamp in the operating state is provided for lamp ignition.