Patent ID: 6483256
Filing Date: 2002-11-19
Classification: H05B

Abstract:
Electronic ballast for gas discharge lamps with heatable elements, which has the following features:a DC supply (DC) between an intermediate circuit potential (P) and a reference potential (E), two series-connected electronic switches (S1, S2) which form a half bridge with a midpoint potential (M), one of the switches (S1) being connected to the intermediate circuit potential (P) and the other (S2) being connected to the reference potential (E), and the switches (S1, S2) switching on and off alternately such that an AC voltage is produced at the midpoint potential (M), a filament transformer (L11, L12, L13) with a core which, on the secondary side (L12, L13), outputs energy to the filaments (W1, W2) and on the primary side (L11) draws its energy from the AC voltage generated by the half bridge, characterized in that the core of the filament transformer has an air gap which is active with reference to the electrical data of the filament transformer (L11, L12, L13).