具有電流模式平滑轉換之雙輸入與改善充電時間之切換式鋰電池充電器

Abstract

隨著對於行動裝置，如智慧型手機、平板電腦和筆記型電腦的需求持續上升，鋰電池做為一個對前述裝置的供應能源來源，一直都在現今科技發展中扮演著重要的角色。同樣的，對於鋰電池充電器的設計規格要求也逐漸地變得比以往更加的複雜。除了對於高能源轉換效率的要求之外，對於充電時間的減少、多能源來源使用的可行性、充電電流的準確性，以及如何做到在充電模式間的平滑轉換，無庸置疑的是對於鋰電池充電器設計者的重要課題。 本論文分別呈現出兩款鋰電池充電器，一為具有雙輸入能源使用性的鋰電池充電器，以及另一款具有充電時間減少的鋰電池充電器。此兩者皆採用所提出的新類電流模式平滑轉換方法，以解決在充電模式間切換時的模式震盪。兩款鋰電池充電器都採取脈波頻率調變方法，以減少在補償元件的使用與簡化穩定度分析。第一款充電器使用適應性關閉時間控制方法以減少在充電電流的誤差。在轉換效率的考量下，第二款充電器以固定關閉時間方法，搭配上加速開關頻率控制來達成截止電流準確加強與充電時間減少。 於本論文所呈現之晶片，皆透過台灣積體電路公司所提供之0.35微米2P4M的標準互補式金氧半製程來完成。

With the growing demands of portable devices, such as smart phones, tablets and notebooks, lithium battery, being an energy source for the previously mentioned devices, always plays an important role in the recent technology development. Also, the specification requirements of the battery charger have become more complicated than ever before. Besides the high energy transfer efficiency, the decrement of the charging time, multi-source-using capability, charging current precision, and smooth transition between mode switching are definitely necessary issues for battery charger. This thesis presents two switching battery chargers with dual-input source-using capability and charging time reduction techniques, respectively. Both of these works adopt the newly proposed current-mode smooth transition method to solve the oscillation between charging mode switching. The pulse-frequency-modulation is utilized in both works to reduce the requirement of extra compensation elements and simplify the stability analysis. The adaptive off time control technique to reduce charging current error is presented in the first work. As for the efficiency concern, the constant off time with boost switching frequency control is implemented in the second work to achieve precise end-of-current and reduce charging time. The chips presented in this paper were fabricated by Taiwan Semiconductor Manufacturing Company （TSMC） 0.35μm 2P4M 3.3V mixed‐signal CMOS process.