具有主動式電感電流感測器及可適性控制模式切換機制之自我震盪直流對直流轉換器

An Adaptive Mode-Hopping, Self-Oscillating DC-DC Converter with Full Inductor-Current Sensing Technique

莊凱傑(Kai-Jie Chuang)

指導教授 ： 吳紹懋

元智大學/電機通訊學院/電機工程學系/碩士(2009年)

https://doi.org/10.6838/YZU.2009.00007

摘要

本篇論文提出一個具有可適性模式切換機制及具有自我震盪功能之直流對直流轉換器。此直流對直流轉換器可以快速啟動達到穩定，並在負載突然改變時，具有較快的暫態響應。迴路控制電路中包含多路檢測器及主動式電感電流感測器。利用此電流感測器的技術來限制最大及最小電感電流並且感測負載電流大小。
在此提出的直流對直流轉換器中，總共有三種控制模式被建構以求最佳的轉換效率。藉由可適性模式切換機制，連續導通模式及不連續導通模式可自動地切換於高負載和輕負載的情況。而當轉換器處在極輕負載時，可選擇待命模式來降低切換損提升轉換效率。本篇論文亦提出各個操作模式下之轉換效率分析與討論。根據模擬的結果，此直流對直流轉換器的效率高達93.5%，且最大輸出漣波電壓在22毫伏以下，而輸出電流範圍在50mA到350mA之間。在輸入電壓範圍在2.4V到4.2V之間，直流對直流轉換器之操作頻率為0.3到1.7百萬兆赫。此直流對直流轉換器以TSMC 0.35-um 2P4M CMOS製程實現，晶片大小為1.97mm2。

關鍵字

電流感測器 ； 模式切換機制

並列摘要

An adaptive mode-hopping and self-oscillating DC-DC converter is presented in this thesis. This converter had fast transient response and system stable response. A multi-detector and a full inductor-current sensing technique area are applied on the loop controller of this DC-DC converter. The inductor current level is detected by active full inductor current sensor, so as to limit the maximum and minimum inductor current.
Three control modes are constructed for reaching the best efficiency distribution to load condition. The proposed adaptive mode-hopping mechanism activates the converter to switch between CCM and DCM modes when necessarily during normal operation. The idle-mode is utilized at every light load to reduce the switching losses and enhance the conversion efficiency. It is deduced from simulation results that the efficiency of the DC-DC converter can be up to 93.5% on the conditions that the maximum peak-to peak output voltage ripple is less than 22mV and the output current ranges are between 50mA and 350mA. The DC-DC converter operates at a frequency ranging from 0.3 to 1.7MHz and a supply voltage ranging from 2.4 to 4.2V. The DC-DC converter was implemented in TSMC 0.35-μm 2P4M CMOS process with die size of 1.97 mm2.

並列關鍵字

current sensor ； mode hopping mechanism

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