Circuit arrangement for starting and operating a low-pressure discharge lamp

摘要

Electronic ballast devices for discharge lamps are produced for the specific purposes of application in each case with a high outlay in terms of circuitry. The novel circuit arrangement which is distinguished by little outlay and high efficiency (performance) is to make it possible to start the lamp in a preserving (gentle) manner. According to the invention the object is achieved in that a two-port (two-terminal network) (Z1) which contains at least one PTC conductor (R5) is connected, on the one side, to a circuit point of the load circuit of the circuit arrangement and, on the other side, at least via one diode (V3) to the positive terminal (1) and/or via a diode (V4) to the negative terminal (2) of the DC voltage source for supplying the circuit arrangement. The circuit arrangement is suitable for low-voltage discharge lamps which have at least one inductance connected in series with the lamp and at least one capacitor connected in parallel to the lamp and in series to the lamp electrodes.