| 摘要 |
An electrical circuit (10), for supplying power to at least one light source (L) having a filament with a light intensity level selectively variable in a range between a minimum value and a maximum value, is protected from anomalous operating conditions by detecting (S4, S1) the output power of said power supply circuit (10) reaching an upper threshold value and, upon said threshold value being reached, by controlling the circuit in a burst mode including an alternate sequence of active intervals, where the circuit (10) operates to energize said at least one light source (L), and of passive intervals. The duration of active intervals is varied in a manner complementary to the desired light intensity level, so that said active intervals have a minimum duration value when the desired light intensity level is at a maximum and a maximum duration value when the desired light intensity level is at a minimum.
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