| 摘要 |
PROBLEM TO BE SOLVED: To provide a device and method for driving an LED lamp which dynamically adjusts the number of LEDs in an LED string on the basis of a rectified voltage and more closely matches the overall ON-state voltage of the LED string to the rectified voltage, thus increasing utilization efficiency of electric energy.SOLUTION: This invention is for adjusting the numbers of LEDs in an LED string on the basis of a rectified AC voltage. An embodiment comprises a power module, an LED string, a current source and a controller. The LED string has multiple LEDs connected in series that form one major segment and multiple minor segments. The controller is connected to the current source and the LED string, and selectively shorts the LEDs in the minor segments. |
