A Sliding Mode Controlled Buck Converter with Fast Transient Response and Wide LC Tolerance for Portable Applications

應用於手持式電子裝置具有快速暫態響應和寬電感電容耐受力之高穩定性滑模壓降式電壓轉換器

陳衍彬(Yen-Pin Chen)

指導教授 ： 張慶元

國立清華大學/電機資訊學院/積體電路設計產業研發碩士專班/碩士(2010年)

摘要

近年來，伴隨著無線通訊技術的發展與製程的縮小化，可持式裝置也日益受到大眾的喜愛。如何維持長時間的蓄電力並且能提供一個穩定乾淨的電源，與電源管理技術息息相關。一般的電源管理系統往往整合各式各樣的穩壓器，目的是分別用來供應不同區塊晶片之電壓。其中穩壓器的作法主要可分成切換式直流-直流電壓轉換器與線性低壓降穩壓器。切換式直流-直流電壓轉換器可以具有較高的效率，且可以依照使用者喜好而設定出不同的輸出電壓準位。本論文提出ㄧ個簡單且有系統的方式來設計滑模控制直流降壓轉換器電路，此電路可以穩定的操作在連續導通模式(CCM)，並且整合了功率晶體。而滑模控制的重點在於在進入滑模控制底下時，系統可以把所要的狀態變數控制在你想要的範圍之內，如電壓誤差與電壓誤差變化率，可藉由調整power stage的MOS開關來達成要求。在滑模控制下，進入穩態之後電壓誤差與電壓誤差變化率皆控制在所要的範圍之內。藉由本論文所提出的全波電感電容偵測電路、可調式磁滯控制電路等所組成的控制電路，可以使此滑模控制直流-直流壓降轉換器達到快速暫態響應和對外部電感電容(LC)濾波器有強健性，並且不用外部的補償電路，亦即在外部參數有偏移的情況下，仍然能夠提供穩定的輸出電壓。由所提出的磁滯控制方式在所有操作情況下切換頻率都可以維持定值。此電路工作電壓可以在2.5~5.5V範圍中，並且提供5mA~1A的負載電流，操作頻率為300kHz~1MHz，可以滿足lithium-ion電池的應用場合。

關鍵字

滑模降壓式轉換器

並列摘要

For the portable applications, how to maintain the battery life and provide a clean DC voltage are very important. Therefore, the battery life and the stability of the voltage are interrelated to the power management techniques. This thesis presents a simple and systematic approach to design of a sliding mode controlled buck DC-DC converters operating in continuous conduction mode (CCM) with integrated power switches and a fully current sensor, adjustable hysteresis band for the feedback controlled. This controlled sliding mode achieves fast transient response and wide LC (L=3~30μH, C=2~350μF) tolerance without external off-chip compensator. The operating frequency is from 300kHz to 1MHz with supply voltage from 2.5V to 5.5V, which is suitable for lithium-ion battery supply applications. The load current is from 5mA~1A, and the switching frequency is constant under all operating condition with proposed adjustable hysteresis band controlled.

並列關鍵字

sliding mode dc-dc buck converter

參考文獻

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