高迴轉率之可程式低壓降線性穩壓器

PROGRAMMABLE OUTPUT LOW DROPOUT REGULATOR WITH SLEW-RATE ENHANCEMENT CIRCUITS

羅謝誠(Sei-Cheng Luo)

指導教授 ： 蔡明傑

大同大學/電機資訊學院/電機工程學系所/碩士(2010年)

摘要

低壓降線性穩壓器常使用在各種電子產品上，尤其在可攜式電子產
品為重要的驅動電路，而可攜式電子產品在電池供應的情況下必須提高
轉換效率且降低功率消耗為主要目標。此種線性穩壓缺點之ㄧ為僅有一
種輸出電壓，對於不同需求的電路而言必須再對輸出電壓做分壓方式取
得，此法對於輸入電源必定形成某重程度上的功率消耗，因此本篇論文
設計一個可程式化的能隙參考電壓電路，提供給低壓降線性穩壓器作為
參考電壓源，藉此達到不同電壓的輸出。參考電壓源使用PTAT參考電
壓電路，並結合3bit數位類比電流轉換器，達到可程式化的目的。因此
輸出具有8種電壓，分別為1.8V~2.5V。採用的是推挽式輸出放大器，可
提高迴轉率與降低靜態電流。本電路使用台積電0.35μm 2P4M CMOS製
程模擬，輸入電壓3.3V下，最大輸出電流為100mA，負載電容在470PF
下，迴轉率小於2μs。

關鍵字

低壓降線性穩壓器 ； 可程式能隙參考電壓 ； 迴轉率

並列摘要

Low dropout linear regulators are often used in a variety of electronic
products, especially in mobile system products as an important driver. To
prolong the battery life, power efficiency of low dropout regulators can be
improved by reducing the power consumption. Linear regulator is only one
step down and only one output voltage, the circuits for the different needs
have to divide bias on output voltage. The design specifies a programmable
bandgap reference voltage circuit to provide a reference voltage to low
dropout linear regulator to achieve a different voltage output. Reference
voltage operational amplifiers uses PTAT voltage circuit with 3bit digital to
analog current converter, to achieve the purpose programmable and the
output voltage with 8, respectively 1.8V ~ 2.5V. The LDO used push-pull
output amplifier which increase the slew rate and reduce the quiescent
current by TSMC 0.35μm 2P4M CMOS process technology. The input
voltage 3.3V and maximum output current of 100mA of the slew rate of less
than 2us while load capacitance 470PF.

並列關鍵字

Low dropout regulator ； Programmable Bandgap ； Sle

參考文獻

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[3] Y. C. Wu, C. Y. Huang, B. D. Liu “A Low Dropout Voltage Regulator with Programmable Output,” in proc. IEEE Conference on ICIEA, May. 2009, pp. 3357-3361.

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[5] W. J. Huang, S.H. Lu, and S. I. Liu, “A Capacitor-free CMOS Low Dropout Regulator with Slew Rate Enhancement,” in proc. Int. Symp. VLSI Design, Automation and Test, pp.1-4, Sep. 2006.

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