本論文研究題目為數位一次側控制返馳式發光二極體驅動器之研究與設計，詳細探討了LED driver須具備的功能：固定導通時間控制功因改善、準諧振效率提升以及定電流控制於類比文獻的做法，再從類比研究議題衍伸至數位化的研究現況，並探討各種實現方式上的優劣差異。
本論文作品根據文獻探討結果，設計一符合現行LED driver功用與規格標準的數位一次側回授LED driver。針對延遲誤差補償，本作品提出一種新的實現方式，相較於過去作法，導通時間補償方式(On-Time Compensation)可充分發揮固定導通時間控制法的優勢，直接調變開關導通時間來解決延遲問題，省略過去作法所需要的複雜運算，並達到同樣的效果。此外，固定導通時間控制功因改善上採用數位限頻機制，不需要偵測其他訊號就可以達到優化效果，以降低成本。最後以FPGA搭配PCB系統完成控制驗證與系統量測。
本作品貢獻為學術界第一個完整實現數位控制的LED driver，包含現今市售產品所需具備的主要功能，且都提出數位的解決方案。在性能的比較上，本作品的PF與THD已不輸業界數位的產品；而Line Regulation結果為±3%，與Load Regulation結果為±2%上的表現尚可，與其他產品比較起來差異不大但仍有進步的空間。

In this paper, the research topic is study and design of digital primary-side controlled flyback LED drivers. The main functions of LED drivers in analog: constant on-time control power factor improvement, quasi-resonant efficiency improvement and constant current control, are discussed in detail. Then, change the issue to digital control, and explore the differences between the various implementation methods.
According to the results of the literature research, a digital primary-side feedback LED driver, which conforms to the functions and specification standards of commercial products, is proposed in this paper. For the delay error compensation, this work proposes a new implementation method. Compared with the past practice, On-Time Compensation can fully exploit the advantages of the constant on-time control, directly adjust the switch on-time to solve the delay problem. It can not only omit the complex operations required by past practices but also achieve the same effect. In addition, the constant on-time control is improved by digital frequency limit mechanism. The optimization effect can be achieved without detecting other signals to reduce the cost. Finally, the verification is completed with the FPGA and the PCB system.
This work is the first fully digital control LED driver in the academia, including the main functions required for today's commercially available products. In terms of performance, power factor (PF) and total harmonic distortion (THD) of this work are better than industry's digital products; Line Regulation is ±3% and Load Regulation is ±2%. Both of them are nearly the same to other products, but there is still room for improvement

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