新型低電壓正相降升壓轉換器設計

The Design of New Low-Voltage Positive Buck-Boost Converter

沈濱楠(Bin-Nan Shen)

指導教授 ： 陳建中 ； 黃育賢

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2011年)

摘要

本論文第一個部份提出使用低電壓運算放大器及平均電流控制技術之低電壓正相降升壓轉換器設計，正相降升壓轉換器有別於傳統降升壓轉換器，它改善了傳統降升壓轉換器輸出電壓為負電壓的缺點。利用數位電路對溫度和製程變異的影響度低、對雜訊的敏感度低、功率消耗較低等優點，來降低電路功率消耗與提高電路穩定性。所提出的電路使用平均電流控制技術，不需額外使用斜率補償電路來解決次諧波失真的問題，並且加入了電流感測電路，藉由感測電感上的電流來縮短暫態反應時間，進而改善負載調節率。電路使用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，晶片面積分別為2.46 x 2.46 mm2 (包含PADs)。
本論文第二個部份提出具有模式選擇電路及前饋技術之正相降升壓轉換器設計。利用正相降升壓轉換器可以分別操作在降壓、降升壓、升壓的特性，使用模式選擇電路在固定輸出3.3V的情況下判斷當時電池電量的多寡決定使用何種模式，來降低傳導損失和開關損失。正相降升壓轉換器之三種模式能正常工作在寬廣的輸入電源電壓，因此可以有效地利用電池每單一生命週期，讓使用時間得以延長。加入了前饋技術，讓電源電壓改變時可以縮短暫態反應時間，進而改善線性調節率。電路使用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，晶片面積分別為2.59 x 2.73 mm2 (包含PADs)。

關鍵字

正相降升壓轉換器 ； 低電壓運算放大器 ； 平均電流控制 ； 模式選擇

並列摘要

The first part which is a low-voltage positive buck-boost converter using average- current-controlled techniques is proposed in this thesis. This circuit is different from the traditional buck-boost converter, the shortcoming which is output negative voltage has improved on traditional buck-boost converter. Moreover, the average-current-controlled circuit does not need to use slope compensation technique. The advantages of the low-voltage operational amplifier are lower power dynamic consumption and low supply voltage operation. The proposed low-voltage positive buck-boost converter using the active-current-sensing circuit and average-current-controlled circuit techniques can work stably without slope compensation even when the duty cycle is higher than 50%. The proposed design circuit has been fabricated with TSMC 0.35μm CMOS 2P4M processe, the total chip area is 2.46 x 2.47mm2 (with PADs). The supply voltage is 1.5V, and the regulated output voltage range is from 0.8V-3.3V. Switching frequency is 1 MHz.
The second part of this thesis is a high-efficiency positive buck-boost converter with mode-select circuit and feedforward techniques is proposed. Four power transistors which produces more conduction and more switching losses turn on or off when positive buck-boost converter operates in buck-boost mode. Utilizing mode-select circuit can decrease this problem and let positive buck-boost converter in buck, buck-boost or boost mode. By adding feedforward techniques, the proposed circuit can improve transient respones when supply voltage changing. The proposed design circuit has been fabricated with TSMC 0.35μm CMOS 2P4M processe, the total chip area is 2.59 x 2.74mm2 (with PADs). The output voltage is 3.3V, and the regulated supply voltage range is from 5V-2.5V. Switching frequency is 500 kHz.

並列關鍵字

positive buck-boost converter ； low-voltage operational amplifier ； average-current-controlled ； mode-select

參考文獻

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