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。
本篇論文提出一個數位化之線上溫度/功率調控器。本調控器包含數位化溫度感測器，數位控制之切換式電壓轉換器，與全數位化之調控介面。其中切換式電壓轉換器是利用脈衝調變方式並且搭配數位邏輯運算系統實現動態電壓調控，最大負載電流300mA，其輸出電壓範圍可由0.8V到1.8V。溫度控制部分則是利用數位化比例微分控制器並且搭配一溫度誤差範圍0.12°C至-0.34°C的溫度感測器實現可程式化溫度調控系統，溫度量測範圍可由0°C至120°C。且溫度與電壓輸入訊號皆為數位值以便和數位系統結合，本電路並利用一數位直流-直流遲滯轉換器去調節功率變化，由於數位遲滯直流-直流轉換器所占面積非常小，非常適合於線上溫度/功率調控之應用。
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.
This thesis proposes an on-line digital thermal/power monitoring system. The proposed system includes a digital programmable temperature sensor, digital programmable dc-dc buck converter, and a fully digital thermal/power controller/interface. With the pulse frequency modulation (PFM) control technique and digitalized control circuits, the proposed buck converter can tightly regulate the output voltage and is robust to the process variation. The output voltage range is from 0.8V to 1.8V with the maximum output current of 300mA. With the proposed digital interface and a high accurate 0.12°C to -0.34°C, high conversion rate temperature sensor, the proposed architecture is very suitable for on-line thermal/power monitoring.
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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