Design of Digital Linear Power Supply with Low Current Ripple  

作　　者：Che-Min Kung Yeh-Chen Yeh Wen-Tien Tsai 

机构地区：[1]Department of Green Energy and Environment Research Labs,Industrial Technology Research Institute,Hsinchu County 310401,Taiwan

出　　处：《Journal of Mechanics Engineering and Automation》2023年第2期32-39,共8页机械工程与自动化（英文版）

摘　　要：A linear power supply is a circuit architecture directly driven by AC. Multiple high-voltage LEDs (light-emitting diodes) are connected in series to withstand the input voltage. The LEDs are divided into multiple segments through a segment switching mechanism to adapt to the pulsating DC changes after bridge rectification. Due to imperfect switching between control signals, there may be signal overlap or misalignment, which reduces circuit performance and component lifespan. Firstly, signal overlap occurs when the next segment opens before the previous segment is about to close. This state causes overlapping intervals where two segments of current combine, resulting in a high combined current that can lead to significant power losses and generate heat, potentially reducing the lifespan of the components. Secondly, signal misalignment occurs when the next segment prepares to open after the previous segment has completely closed. In this state, there is a time gap with no current flow, resulting in reduced output power and exacerbating LED flickering. Both of these undesirable phenomena introduce ripple into the LED output current. In this paper, a digitalized design is proposed to precisely compensate for the timing between alternating signals, significantly reducing output current ripple. This approach helps enhance power supply performance, extend component lifespan, and reduce LED index flicker.

关 键 词：LED LINEAR FLICKER direct AC current ripple 

分 类 号：TN3[电子电信—物理电子学]