低壓降線性穩壓器已經被廣泛的使用在各種3C產品上，特別是近幾年流行的可攜帶式電子產品，此時延長電池的續電能力是非常重要的。由於電子產品的電路系統上有許多不同的模組，所以需要不同電壓位準的直流供應電壓。因此，一個電路系統會用到許多個穩壓電路，所以穩壓 IC 的效能及穩定特性在電子產品中扮演舉足輕重的腳色。
在類比電路設計中我們可分為以下幾個部份： A/D、D/A、電壓源、電流源、放大器等，而電壓源在這幾個方面中是非常重要的，因為二極體、電阻、電容和電晶體等電子元件都會受到溫度的變化而影響特性，就算溫度只有微小的變化也都可能造成整個系統無法運作，所以在類比電路中一個穩定的電流源或電壓源是必要的。
本論文的研究重點為設計一低壓降線性穩壓器，用以提供一個穩定的電壓，低壓降線性穩壓器包括參考電壓源、誤差放大器、分壓回授電阻以及功率電晶體。本論文使用台積電65奈米製程設計，操作電壓為2.5伏特，因線性穩壓器具有電路架構簡單、輸出漣波低、外部元件少、功率消耗低‧‧‧等特性，所以很適合用在可攜式電子產品中。

Low Dropout Linear Regulator has been widely used in a variety of 3C products, especially the popular portable electronic products in recent years, where extending battery life is the most important thing.Since there are many different modules on electronic circuit, so they need a variety of voltage levels of the DC supply voltage. Thus, the circuit of a system required use multiple voltage regulator circuit, voltage regulator IC plays a very important roles in the performance and stability characteristics of electronic products.
In the field of analog IC design can be divided into several parts: A / D, D / A ,voltage source, current source, amplifier, and a voltage source which is the very important, because a stable voltage or current source is the basis of analog circuits. Electronic components diodes, resistors, capacitors and transistors, etc. are affected by changes of temperature. Analog design for only a few degrees Celsius temperature difference can cause a tremendous impact.
In this paper, the research focus on the design of a low-dropout linear regulator with a stable voltage, the former includes voltage reference generator, error amplifier, feedback network, and Power MOS and is implemented with TSMC 65nm process, operating voltage at 2.5 volt. Due to the linear regulator circuit having a simple structure, low output ripple, less external components, low power consumption and other characteristics. So it is suitable for using in portable electronic products.

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