電荷幫浦升壓轉換器與飛馳電容式降升壓轉換器之設計

Design of Charge-Pump Boost Converter and Flying-Capacitor Buck-Boost Converter

劉安(An Liu)

指導教授 ： 黃育賢

共同指導教授 ： 陳建中

國立臺北科技大學/電資學院/電腦與通訊研究所/博士(2014年)

摘要

論文第一部份提出一種新型的連續導通模式的低漣波(ripple)高效率電荷幫浦(charge pump)升壓轉換器。所提出的轉換器的主要組成部分包括一個兩倍升壓的電荷幫浦和一個低通LC濾波器。此提出的轉換器具有正電壓且低漣波的輸出電壓，其電壓升壓比為（1 + D），其中D是切換控制訊號波形的責任週期。由於此轉換器的儲能電感與負載在所有時間皆保持連接，並且儲能電感亦一直保持連接到的電荷幫浦輸出電源(Vin與2Vin之間變動)，故所提出之轉換器總是工作在連續導通模式中，因此輸出電壓漣波較小且輸出電容上的電流應力(current stress)亦較小。此電路採用TSMC 0.35μm 2P4M CMOS製程來實現，晶片面積為1.49mm×1.49mm(含PADs) ，其工作頻率為1MHz，此電路轉換效率可達到90.95 ％，且其暫態響應時間約只有7μs。
本論文的第二個部份提出的電路為利用虛擬電流動態加速的脈波寬度調變(PWM)飛馳電容式降壓-升壓轉換器。此轉換器的電壓轉換比為2D，其中D是切換控制訊號波形的責任週期。此轉換器改善傳統切換式電容(switch capacitor)型轉換器效率較差的本質，以及傳統電感降升壓(buck-boost)轉換器穩定性較差的本質，所提出的轉換器的動作行為類似於傳統的同步整流降壓轉換器，因而具有非常高的系統的穩定性。且不同於傳統負輸出電壓的電感型降壓-升壓轉換器，提出的轉換器具有正的輸出電壓。此外，此改良架構的轉換器的控制電路，使用虛擬電流動態加速技術，可於負載於重負載和輕負載之間變化時，實現快速的暫態響應。本電路使用TSMC 0.35μm 2P4M CMOS來實現，晶片面積為1.5 mm× 1.5 mm (含PADs)。實驗結果顯示，提出的轉換器輸入電壓為3.3V，輸出電壓的範圍為1.0V-4.5V，其切換頻率為1 MHz，轉換效率最高可達到89.66%。應用虛擬電流動態加速技術的控制器，可達到當負載電流變化200 mA時，暫態響應小於2 μs的優異表現。

關鍵字

升壓轉換器 ； 降升壓轉換器 ； 電源管理晶片 ； 電荷幫浦

並列摘要

In this first part of this thesis, a new continuous conduction mode (CCM) low-ripple high-efficiency charge-pump boost converter is presented. Its components include a double voltage charge pump and a low pass LC filter. The voltage boost ratio of the positive low-ripple output voltage of the proposed converter is (1+D) where D is the duty cycle of the control switching signal waveform. Since the energy storage inductor is connected to the power source and the load at all times, the proposed converter always operates in CCM, the transient responses are fast, and the current stress on the output capacitor is reduced and the output voltage ripple is small. In this paper, the operation principles of the CCM low-ripple high-efficiency charge-pump boost converter are described in detail. Its circuitry is designed and implemented with a TSMC 0.35µm CMOS processes whose operation frequency is 1MHz. The circuitry is simple and the power conversion efficiency is up to 90.95%, and the transient response is only 7µs.
In this second part of this thesis, a fast transient response flying-capacitor buck-boost converter is proposed to improve the efficiency of conventional switched-capacitor converters. The voltage boost ratio of the proposed converter is 2D, where D is the duty cycle of the switching signal waveform. The behavior of the proposed converter is similar to a conventional synchronous-rectified buck converter, thus the stability of the system is very high. It has positive output voltage, which is different from the negative output voltage of a conventional buck–boost converter. Furthermore, the proposed structure utilizes pseudo-current dynamic acceleration techniques to achieve fast transient response when load changes between heavy load and light load. The switching frequency of the proposed converter is 1 MHz for 3.3V input and 1.0V-4.5V output range application. Experiment results show that the proposed scheme improves the transient response to within 2μs and the total power conversion efficiency can be as high as 89.66%. The proposed converter has been realized by a 2P4M CMOS chip by 0.35μm fabrication process with total chip size of about 1.5 mm × 1.5 mm, PADs included.

並列關鍵字

boost converter ； buck-boost converter ； Power Management ICs ； charge pump

參考文獻

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