應用於可攜式並具有新型主動式電流感測器之高效率直流對直流轉換器

A High-Efficiency CMOS DC-DC converter with a New Active Current Sensor for Portable Applications

張崇傑(Chung-Chieh Chang)

指導教授 ： 吳紹懋

元智大學/工程學院/電機工程學系/碩士(2004年)

摘要

本篇論文提出一個應用於可攜式並具有主動式電流感測器技術之高效率直流對直流轉換器，此轉換器是利用主動式電流感測器和控制電路去檢測負載電流和電壓的變化，藉以達到最大電流限制以及提高整體效率。並且利用迴授機制去使輸出電壓穩定在一個預期的準位。
在此次提出的直流對直流轉換器中，包含了主要的架構有功率電晶體、驅動電路、數位脈波頻率調變器、多路檢測器、主動式電流感測器以及能隙參考電壓電路。此轉換器的效率可以高達95％以上且輸出變化量在23毫伏以內。因此是非常適用於消費性電子產品及可攜式產品的應用上。此晶片是以台灣積體電路公司零點三五微米兩層多晶矽四層金屬互補式金屬氧化物半導體製程來實現，本電路之供應電壓可從2.4伏特操作至4.2伏特。此轉換器可以產生1.3伏特至3.5伏特的輸出電壓範圍、並且迴授電壓穩定在1.2伏特、輸出電流範圍也在連續導通模式下從50毫安培至500毫安培。操作頻率在二十五萬赫茲至一百五十萬赫茲，面積為小於0.9 mm2。

關鍵字

電流感測器、直流對直流轉換器、能隙參考電壓電路、互補式金屬氧化物半導體

並列摘要

In this thesis, we design and implement a high-efficiency CMOS DC-DC converter with a new active current sensor. This converter employs a new active current sensor and control circuit to detect load current and load voltage in order to reach maximum current limit and increase efficiency.
In the proposed DC-DC converter, the key building blocks includes power switch, driving circuit, digital pulse-frequency modulation, Multi-Detector, active current sensor and Band-gap reference. The efficiency of the converter is up to 95% with the variation of the output voltage less than 23 mV, suitable for the applications of consumer electronic products and portable products. This chip and all the devices were fabricated in the TSMC 0.35-μm DPQM CMOS process from the supply voltage ranging from 2.4V to 4.2 V. The DC-DC converter can generate output voltage between 1.3V-3.5V and the feedback voltage is fixed at 1.2V while output current ranges between 50mA and 500mA with operation mode of CCM (Continuous Conduction Mode). The DC-DC converter operates at a switching frequency ranging between 250 and 1500 KHz, area is less than 0.9 mm2.

並列關鍵字

active current sensor、DC-DC、Band-gap、CMOS

參考文獻

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