單晶片溫度感測器中的正比絕對溫度參考電壓之設計與製作

Abstract

這篇論文使用0.25微米互補式金氧半標準製程設計並實現了一個正比絕對溫度參考電壓源．過去的研究提出將金氧半電晶體操作在弱反轉區可用來取代傳統電路中的雙極性電晶體以實現正比絕對溫度的電路．然而，這些電路在高溫時都會有非線性的現象產生，本論文提出的電路運用了一個補償的技巧以改善其在高溫時的線性度．量測結果顯示此電路的線性工作區間可延伸到至少155□C，此電路只需要校正因製程飄移所產生的偏移電壓．因此，製程後段所需的校正工作將可減低至最低．另外，此電路可以容易的與其他任何的數位系統整合．

A pure CMOS proportional-to-absolute temperature (PTAT) reference circuit has been designed and implemented in a standard 0.25-□m CMOS technology. Previous research has proposed the use of MOS transistors operating in the weak inversion region to replace the bipolar devices in conventional PTAT circuits. However, such solutions often have nonlinearity problem in high temperature. The proposed circuitry applied a compensation technique to enhance the linearity of high temperature behavior. The experimental results show the linear range of the voltage output has been expand to at least 155°C, which implies that the temperature sensor requires calibration only of its offset. Thus, the effort for after process calibration is minimized. The proposed circuit can be integrated to any digital systems with minimal efforts.