| 摘要 |
The oscillatory lamp circuit is supplied by a mains-fed rectifier. Alternate current half-cycles are controlled by identical circuits (1), each having a power transistor (Ta), with current monitored (5a, 5b), via an integrator (6), by a comparator (7) using a reference (Iref) proportional to the rated lamp current. Comparator signals (s2) provide one input to a bistable device (8); another (s1) emanates from a zero-voltage detector (3, 4). the bistable unit responds to these signals by alternately blocking and opening, respectively, the lamp current path (Bla-B2a), via the MOSFET gate (g). For start-up, random pulse generators (11) are connected t the bistable voltage reference input in each control circuit (1), via an OR gate (10). Conduction begins in the first transistor to receive a signal pulse.
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