A Cost-Efficient LED Driver with Low-Flicker

A Cost-Efficient LED Driver with Low-Flicker

The market for LED lighting has been growing steadily due to its high efficiency and long life. However, there are still several technical challenges to overcome, especially with grid-powered LED drivers. The line-frequency flicker has become a health issue. Although line-frequency flicker is usually invisible, it can be picked up by the retina, causing visual fatigue. Therefore, LED drivers need to produce constant power to avoid flicker. In this paper, a hybrid driver circuit with an isolated PFC flyback and a linear constant current LED driver is proposed with the novel dynamic control method. The new approach enables the linear constant-current LED driver to operate with high efficiency. Since the linear constant-current LED driver has no concern about high-frequency, high-voltage, and high-current switching. It minimizes EMI risk and reduces the system complex and cost. Finally, a low flicker 25W LED driver with DALI 2.0 interface is completed.