隨著金氧半導體製程和設計複雜度的演進，晶片面積不斷縮小而耗能則不斷增加，如何解決超大型積體電路運作時產生的熱能所帶來的影響，已經成為設計上不可忽略的重要課題。高熱不僅會降低系統運作的效率，更有可能造成晶片燒毀，為了防止上述狀況的發生，對系統溫度的即時監測實屬必要。
本篇論文的第一個部份提出了一個無需傳統數位/類比轉換器與帶差參考電壓源的金氧半導體溫度感測器，第二個部份則為此感測器在即時溫度監控系統上的應用。經兩點校正後，在0 ℃至125 ℃的範圍內此溫度感測器的誤差可在±0.8 ℃內。此溫度感測器包含了一個運用金氧半導體的溫度特性所建的□VGS產生器，和一個用以產生數位訊號的電壓/時間轉換器和時間/數位轉換器。此感測器僅佔去0.05 mm2的面積、消耗120 □W的功率且取樣頻率高達3K 樣本/秒，上述特性使其相當適合整合在超大型積體電路中提供溫度資訊。在提供一個100 MHz的外部時脈下此感測器可達到0.025 ℃/LSB的最佳解析度。
除此之外，本篇論文也將此溫度感測器整合在線上熱監測系統中以驗證其效能。模擬結果顯示了系統的溫度的確受到持續的量測與控制，若溫度上升超過某一限制，此線上熱監控機制會動態地調整系統的供應電壓以降低系統的消耗功率，使系統的溫度降低並穩定至可接受的範圍，以達成防止系統過熱的目的。

Due to the advance in CMOS technology and design complexity, more power is dissipated in smaller die area, thus the thermal density of modern VLSI systems is becoming a critical issue. High die temperature can not only degrade circuit performance but also leads to thermal runaway. Therefore, continuous monitoring of die temperature is crucial.
In this thesis, a CMOS smart temperature sensor without conventional ADC or bandgap reference is proposed for thermal management of VLSI system. The accuracy is within ±0.8 °C over the temperature range of 0 °C to 125 °C after two-point calibration. The sensor consists of a □VGS generator that utilizes the temperature characteristics of CMOS transistors, a voltage-to-time converter and a time-to-digital converter to provide digital output. A small die area of 0.05 mm2, an extremely low power consumption of 120 □W and a high conversion rate of 3K conversion/s make this temperature sensor very suitable for VLSI integration. The sensor features a finest resolution of 0.025 °C/LSB with a 100 MHz external reference clock.
In addition, the proposed temperature sensor is integrated into an on-line thermal monitoring scheme to verify its performance. Simulation shows that the circuit is under continuous monitoring of the proposed temperature sensor. If the die temperature reaches a certain limit, the on-line thermal monitoring will invoke supply voltage scaling to decrease the circuit power dissipation, thus the die temperature will decrease to a constant stable value.

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