在本論文中，我們提出了一種具有低溫敏感性的低功耗、超小面積片上張弛振盪器的開發設計。該電路受益於新引入的自動優化流程，可有效調整 MOSFET 參數。為了克服大面積消耗無源元件的挑戰，我們用 MOS 虛擬電阻器和 MOS 電容器取代電阻器和電容器，從而使設計變得更加緊湊。為了補償振盪器固有的 PTAT 行為，我們採用了通過充當虛擬電阻器的 MOSFET 實現的 CTAT 偏置電路。在 TSRI（台灣半導體研究所）的協助下，所提出的設計已在 TSMC 0.18μm 標準 CMOS 工藝中成功製造。該張弛振盪器在-25℃至+125℃的溫度範圍內實現了11.39MHz的穩定頻率工作，溫度係數為28.17 ppm/℃。在 1.3V 電源電壓下，其功耗為 243.1μW。值得注意的是，這種創新電路設計佔用的超小核心芯片面積僅為0.009mm2。通過自動優化，我們通過一系列Python程序減少了MOSFET調整大小問題的大量時間消耗。通過這項工作，我們顯著推進了振盪器設計，以緊湊的外形尺寸提供了更高的性能、溫度穩定性和效率，非常適合空間受限的應用。

In this thesis, we present a developed design of a low-power, ultra-small area on-chip relaxation oscillator with low-temperature sensitivity. The circuit benefits from a newly introduced automatic optimization process that effectively resizes MOSFET parameters. To overcome the challenge of large area-consuming passive components, we replace resistors and capacitors with MOS virtual resistors and MOS capacitors, resulting in a significantly more compact design. To compensate for the inherent PTAT behavior of the oscillator, we employ a CTAT biasing circuit implemented through a MOSFET which act as a virtual resistor. The proposed design is successfully fabricated in a TSMC 0.18μm standard CMOS process with the assistance of TSRI (Taiwan Semiconductor Research Institute). This relaxation oscillator achieves a stable frequency operation of 11.39MHz over the temperature range of -25℃ to +125℃ with the temperature coefficient of 28.17 ppm/℃. It has a power consumption of 243.1µW at a 1.3V supply voltage. Notably, this innovative circuit design occupies an ultra-small core chip area of just 0.009mm2. With automatic optimization, we reduce the large time consumption for MOSFET resizing issue with a series of python programs. Through this work, we significantly advance oscillator design, offering improved performance, temperature stability, and efficiency in a compact form factor ideal for space-constrained applications.

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