隨著超大型積體電路朝向高密度、多用途之系統晶片發展，晶片功率的管理已成為電路設計的重點之一，如果不仔細處理由功率消耗所產生的熱能，可能會使得電路元件被破壞進而影響整個系統的安全性，也會導致後續處理問題的成本增加。為了降低溫度變化對電路造成的影響，在超大型積體電路裡面內建溫度感測器來監控晶片溫度的變化，可以增加系統的可靠性及使用時間。
本論文提出一種不需恆溫校正之具電壓校正之時域智慧型溫度感測器以降低大量製造時的成本。本溫度感測器主要包含一弛張震盪器在正、負溫度係數參考電壓間震盪，以產生與溫度相關之脈衝寬度，之後再藉由時間至數位轉換器得出對應之數位輸出。晶片校準方面將改採電壓校準以取代恆溫校準，俾便降低製造成本。以TSMC 0.18um 1P6M製程實現電路，供應電壓1.8V，轉換速度高達850k Hz、每次轉換只需318pJ，面積也只需0.095mm2，解析度為0.48°C，感溫範圍從-40°C到120°C，誤差精確度可在-0.9°C ~ +0.8°C內，其效能竟然還優於某些採用單點或雙點校正之作品！況且，對絕大部分商業應用而言，溫度感測器的誤差只被要求落在±1°C之範圍。總之，本設計兼具低成本與高效能，可望為不需恆溫校正之時域智慧型溫度感測器立下傲人之里程碑。

As VLSI chips pursue high integration density and more functionalities, thermal management becomes an inevitable trend for chip design nowadays. Without proper supervision, the heat built up by undue power consumption may seriously damage the device robustness or even burn out the chip. To reduce the risk of overheating, VLSI chips gradually integrate temperature sensors for thermal monitoring to enhance their reliability and life span.
A voltage-calibrated time-domain smart temperature sensor without the need of any fixed calibration temperature is proposed in this thesis to reduce the cost of massive production. The sensor mainly composes of a relaxation oscillator oscillating between two CMOS-based CTAT and PTAT references to generate temperature-dependent output pulses. A succeeding time-to-digital converter is utilized for digital output coding. Voltage-domain instead of temperature-domain calibration is adopted to substantially reduce the calibration cost.
Fabricated in a TSMC 0.18-um standard 1P6M CMOS process, the proposed sensor is measured to operate at a 850k samples/sec high speed. Moreover, each sample consumes only 318pJ. The active area is merely 0.095 mm2 and the resolution is 0.48°C with an inaccuracy less than -0.9°C~0.8°C over a wide temperature range of -40°C~120°C. Its performance is superior to some chips with one- or two-point calibrations. A milestone is thus established for time-domain smart temperature sensors without the need of any fixed-temperature calibration.

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