Discharge lamp ignition and supply circuit having a PTC resistor

摘要

In a circuit for an inductively stabilized discharge tube (1) provided with two preheatable electrodes (2, 3) the ends of one electrode (2) are connected via a first capacitor (22) and a second capacitor (24), respectively, to the corresponding ends of the other electrode (3). The second capacitor (24) remote from the supply is shunted by a PTC resistor (23). The discharge tube (1) and inter alia the PTC resistor (23) form part of a lamp unit. The discharge tube (1) ignites readily even at low ambient temperatures. In the lamp operating condition, the influence of the PTC resistor (23) is neglible.