一個應用於-55°C到125°C操作在1.8伏特、53.4微瓦、0.25°C解析度之全CMOS溫度感測器

Abstract

一個低功率消耗且精密度高的溫度感測元件在環境溫度量測以及在生物醫學領域之應中辦演著不可或缺的角色，隨著積體電路技術(IC Technique)的進步，傳統的溫度感測器已經不適用於整合在低功率超大型積體電路(Low power VLSI)當中，因此，如何能設計出適用於低電壓、低功率消耗且易於整合在先進晶片系統當中的溫度感測器是一個熱門的研究方向。本篇論文提出一個適用-55°C~125°C之低功率全CMOS溫度感測器，並透過台積電0.18微米製程實現。 本篇論文提出的電路由高線性度的類比前端(Analog Front-end )廣範圍溫度感測器與後端的三角積分類比數位轉換器所組成。類比前端的溫度感測器以一個低功率的全CMOS PTAT架構來達成低電壓低耗電的操作，而後端的三角積分類比數位轉換器是由一個三角積分類比數位調變器與一個SINC3數位濾波器所組成，並以CDS的技巧消去低頻雜訊，而後端的SINC濾波器具備了抑制電力線雜訊的特性。而此電路可操在-55°C~125°C之間，而且有0.25°C的解析度，在功率損耗方面，僅消耗53.4微瓦特，對於每一筆資料轉換所需要的能量為2.67微焦耳。

A low power and high precision temperature sensing unit is an essential unit in environmental and biomedical temperature sensing application. With the development of Integrated-Circuit(IC) technology, the traditional temperature sensor is not suitable for integrating into low power VLSI circuit. Therefore, how to implement a low voltage, low power temperature sensor which can be easily integrated with advanced SOC is an important research. In this thesis, we implemented a 1.8V 53.4uW CMOS temperature sensor with -55°C to 125°C temperature range and 0.25°C resolution which is realized by TSMC 0.18um process. In this thesis, the temperature sensor is composed of a high linearity analog front-end temperature sensor and backend sigma-delta analog to digital converter. The analog front-end sensor is realized by an all CMOS PTAT to achieve low power and low voltage operation. The backend ADC is composed of a sigma-delta modulator and a Sinc digital filter. This circuit can operate from -55°C to 125° with 0.25 resolutions and consume 53.4uW and 2.67uJ for single data conversion.