| 摘要 |
<p>An LED lamp 20 comprises at least three LED elements LD10 - LD33 connected in series between an anode terminal A and a cathode terminal K with at least two bypass resistors R20, R30 connected between at least one of the terminals and respective nodes defined in the series string of LED elements, wherein the LED elements are of differing colour temperatures. The arrangement allows the LED lamp to output light of variable colour temperature when supplied with different current levels by variable current source S1 so as to mimic changes in colour temperature output by an incandescent lamp upon dimming.</p> |
