| 摘要 |
<p>The invention describes an adaptive circuit (1, 1') for driving a lower- voltage DC load (2) from a rectified higher-voltage AC supply(3), which adaptive circuit (1, 1') comprises a charge-storage circuit (21, 21'), which charge storage circuit (21, 21') comprises a first capacitor (C1) and a second capacitor (C2) connected essentially in series, wherein the second capacitor (C2) is connected at least in parallel with the load (2); and an active switch (22, 22') realised as a controlled current source (22, 22') for controlling a load current (I load ) through the load (2) such that, in a closed switch state, load current (I load ) is drawn essentially from the first capacitor (C1) of the charge-storage circuit (21, 21'), and, during an open switch state, load current (I load ) is drawn essentially from the second capacitor (C2).The invention also describes an LED retrofit lamp (4) comprising a connecting means (40) for connecting the lamp (4) to a higher-voltage mains supply signal (U PS );an LED device (2) rated for a lower-voltage supply; and such an adaptive circuit (1, 1') for adapting the higher-voltage mains supply signal(U PS ) to a low-voltage signal (U C2 ) for driving the lower-voltage LED device (2). The invention also describes a method of driving a lower-voltage DC load (2) from a rectified higher-voltage AC supply (3).</p> |
