| 摘要 |
A circuit arrangement comprises four controllable switches (S1, S4) interconnected to form a full bridge. A warm-up operation is carried out in which there is a switch over between the two bridge diagonals (S1, S4; S2, S3) respectively. The gas discharge lamp (EL) is ignited by way of a series resonant circuit (L1, C1) which is coupled to the bridge branch. The actual normal operation is effected by switching over at a low frequency between the switches of the two bridge diagonals (S1, S4; S2, S3), with, moreover, one switch (S1, S2) of the respectively activated bridge diagonal being switched on and off alternately at a high frequency, with this switch (S1, S2) being switched on at the high frequency whenever the current (iL2) flowing by way of the bridge branch has reached a minimum value. |
