本團隊長期以時域型智慧型溫度感測器為研究主軸，多年來的成果不僅包含成本低尚且具有功耗小，適合與其他電路進行統整。此架構受到業界廠商青睞，已成功於去年7月技轉給朋程科技股份有限公司，透過產學合作，將此智慧型溫度感測器應用於車用發電機之溫度監控，提升台灣廠商之國際市場競爭力。
本論文提出應用於車用發電機且具製程校正之時域智慧型溫度感測器，可使用低成本的批次校正(Batch Calibration)來取代傳統之逐晶片單點校正(Chip-by-Chip One-Point Calibration)，可大幅降低校正時間與量產成本，不僅功耗低，且可抵抗製程變異以及隨機不匹配所產生的誤差。主要感溫架構為差動對環形振盪器，此組環形振盪器可以振盪出與溫度成正比之溫敏脈衝寬度，並可利用製程校正電路對製程變異進行校正，最後再藉由時間至數位轉換器轉換出相對應之數位輸出。電路亦使用多重元件佈局技巧以降低製程上的隨機誤差與系統誤差。
本溫度感測晶片使用UMC 0.25-μm CMOS高壓製程實現，操作電壓為4.5V，操作速度為4.128k S/s，每次轉換功耗為0.22J，晶片核心面積為0.961mm2，解析度為0.84C，感溫範圍達-40~150C，其量測誤差經單點校正可在-0.9~0.95C內，經批次校正可在-1.65~2C內。

The focus of our research is mainly on time-domain intelligent temperature sensors. The development of cost-effective and power efficient CMOS sensors are much desired and suitable to be integrated into chips and systems. Our recent research breakthrough for sensors has been transferred to Actron Technology Corporation for further development to enhance the international competition capability of Taiwanese automobile industry.
This thesis focuses on time-domain intelligent temperature sensor with process calibration for automobile power generators. With batch calibration capability, this sensor is able to get rid of the high cost of chip-by-chip calibration. It not only lowers the power consumption but also reduces the impact caused by process variation to provide a cost-effective solution for mass production. A differential ring oscillator is implemented as the temperature sensing core which generates a thermally sensitive output pulse with a width linearly proportional to the test temperature. Furthermore, a process calibration circuit is utilized to eliminate the inaccuracy caused by process variation. A succeeding time-to-digital converter is utilized for digital output coding. Finally, the systematic mismatch is carefully taken care of by precision layout for critical devices.
The temperature sensors are fabricated in a UMC 0.25-μm CMOS high-voltage process with 4.5V operation voltage. The proposed sensor is able to operate at a high speed of 4.128k samples/sec. Each conversion consumes 0.22J only. The core area is merely 0.961mm2. The resolution is 0.84°C. The inaccuracy is measured to be -0.9~0.95C by one-point calibration and -1.65~2C by batch-calibration over a wide temperature operation range of -40C to 150C.

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