摘要 |
A series arrangement of LED loads (LP1-LP4) is coupled between output terminals of a rectifier having its input terminals coupled to a mains supply supplying a low frequency AC voltage. Control means render the LED loads conductive one by one, when the amplitude of the supply voltage increases, and non-conductive one by one when the amplitude of the supply voltage decreases. The first LED load (LP1, LP2) has a forward voltage that is substantially higher than that of the other LED loads. As a consequence, the LED utilization is comparatively high, thus allowing the LED loads used in the series arrangement to be comparatively cheap. |
申请人 |
KONINKLIJKE PHILIPS ELECTRONICS N.V.;KURT, RALPH;TAO, HAIMIN;CREUSEN, MARTINUS, PETRUS |
发明人 |
KURT, RALPH;TAO, HAIMIN;CREUSEN, MARTINUS, PETRUS |