在這篇論文中，我們提出一個可調節的低壓降穩壓器。這個可調節的低壓降穩壓器可以透過外部控制訊號加以控制，進而轉換兩個以上不同等級的穩定輸出電壓。在論文裡有提到不同種類有關於如何實現可調節的低壓降穩壓器的架構，他們不但功率耗損以及面積都不小，而且轉換電壓需要非常長的時間。利用本篇論文所提出的具調節功能之參考電壓產生器以及動態放電路徑所組成的可調節之低壓降穩壓器擁有較低的功率消耗、較低的使用面積、較快速的轉換時間以及很高的延展性。本篇論文裡所設計的具調節功能之參考電壓產生器的架構非常簡單，而且他所消耗的靜態電流只有7微安培，同時參考電壓產生器所產生的參考電壓值所擁有的溫度係數都低於35 ppm/°C。除此之外，當設計者想要增加輸出電壓的數目時，只需要再增加額外的兩極連接電晶體並且適當的調整電晶體尺寸後就可以達到目的。因此利用所設計的具調節功能之參考電壓產生器而做出來的可調節之低壓降穩壓器具有很高的延展性。此篇論文中所設計之可調節的低壓降穩壓器只需要1.6毫秒，從2.5伏特高輸出電壓轉換到1.0伏特低輸出電壓。

In this thesis, we present an adjustable low dropout (LDO) voltage regulator. Through external control signals, the adjustable low dropout voltage regulator can switch between two or more stable output voltages. Several structures of adjustable LDO linear regulators not only consume large power and area, but also require extremely long recovering time from discharging process. Our proposed adjustable LDO linear regulator consisted of a new adjustable reference voltage generator and a dynamic discharging path has the features of lower power consumption, smaller area, shorter transform time and higher extendibility. The structure of the proposed adjustable reference voltage generator is easy to realize and consumes only 7μA. Both temperature coefficients of the generated reference voltages are below 35ppm/°C. Moreover, if designers want to increase the number of output voltages, they only needs to add extra diode-connected transistors in the current structure. The transform time of the proposed voltage regulator is only about 1.6 m sec for output voltage discharging from 2.5V to 1.0V.

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