近年來科技日益發展，物聯網成為當代熱門話題之一，是許多國家及公司相以競爭之焦點。因應可攜式設備與消費性電子產品等需求逐日攀升，因此成本低廉且高精度之智慧型溫度感測器佔有重要的一席之地，尤以超低功耗為主要標的。但如何在優異解析度及低功率消耗之間權衡，乃是一大設計挑戰。
本論文提出一超低功耗時域智慧型溫度感測器架構，透過時間至數位轉換器(Time to Digital Converter, TDC)取代電壓域所需使用的高功率消耗之類比至數位轉換器(Analog to Digital Converter, ADC)，搭配一增益可調時間放大器架構(Variable Gain Time Amplifier, VGTA)，藉以切換不同應用上所需的解析度和轉換功耗，其效能可如類比至數位轉換器，擁有高解析度及較快速的轉換時間，此外也能藉以執行單點校正以大幅壓低量產成本。
本溫度感測晶片使用TSMC 0.18 µm CMOS 1P6M 1.8 & 3.3V標準製程實現，晶片核心面積為0.279 mm2。為了應用於低電壓架構如本實驗室之獵能系統(Energy Harvesting System)，則供應電壓為0.6 V，在後模擬結果下，本論文溫度感測器之功率消耗約為166 nW，可偵測溫度範圍為0 °C ~ 100 °C，其溫度誤差為+0.318/-0.203 °C。轉換時間為4.04 ms，解析度FoM為0.00749 nJ/K2，每次轉換功耗為0.674 nJ，且不需要任何外部參考電路。

With the advance of science and technology, the Internet of Things has become booming in the contemporary era. Due to the increasing demand for portable devices and consumer electronic products, low-cost and high-precision smart temperature sensors play an important role in the market, especially for ultra-low power applications. However, the main design challenge is the trade-off between good resolution and low power consumption.
An ultra-low power time-domain counter-based CMOS temperature sensor is proposed in this thesis, and use counter-based time-to-digital converter (TDC) to replace the high power consumption analog-to-digital converter (ADC) required by the voltage domain temperature sensor. A variable gain time amplifier (VGTA) is included to adjust the resolution and conversion power for different applications. The performance is about the same as ADC-based counterparts. However, it supports one-point calibration to dramatically reduce the cost for mass production.
The temperature sensor is fabricated in a TSMC 0.18 µm standard CMOS process and consumes a chip area of 0.279 mm2. In order to be applied to on-chip energy harvesting system, supply voltage is set to be 0.6 V. The power consumption is 166 nW with an inaccuracy of +0.318 °C to -0.203 °C over 0 °C to 100 °C range by post-layout simulation. With a conversion time of 4.04 ms, a resolution FoM of 0.00749 nJ/K2 is achieved. The sensor does not require any external reference and consumes 0.674 nJ per conversion.

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