Research on a Multi-Output LED Driver and Its Weighted Dimming Strategy

For the application in multi-color spectrum combined dimming of LED plant lighting, a multi-output LED driver based on corresponding spectral demanded by combining constant current Boost circuit unit with injection current Buck circuit unit is proposed in this paper. The operating principle and operating process of the proposed driver, and the relationship between the number of LEDs on the lamp(left) and the lamp (right) and the corresponding spectrum voltage regulation range is analyzed in detail. For the application occasions of plant lighting dimming of the proposed driver, a weighted dimming control strategy is proposed and the principle of the control strategy is analyzed in detail, which high efficiency and wide range dimming can be realized. At the same time, the key parameters of the power stage and the control circuit of the proposed driver are designed. A prototype of the proposed driver with 3-channel output (single-channel rated power 7W) was built. The effectiveness of the proposed combined driver and weighted dimming control strategy has been verified by experimental results.