應用於微機電時脈系統之全數位低功耗溫度感測器

An All Digital Ultra-low-power Temperature Sensor for MEMS-based Clock System Application

蔡昆儒(Kun-Ju Tsai) ； 李瑜(Yu Lee)

《電腦與通訊》 150期 (2013/04) Pp. 53-59

摘要

本論文提出一超低功耗全數位式溫度感測器，其將應用於微機電時脈系統中之溫度感測與補償，藉此降低微機電振盪器因環境溫度變異引起的共振頻率飄移，進而提供一精準的輸出時脈訊號。此溫度感測器中採用環形振盪器式溫度至數位碼轉換機制，於固定取樣時間內將振盪頻率隨溫度改變的特性轉換成數位訊號，再搭配全數位校正電路，以斜率補償、偏移量消除等技術，降低功率消耗與提升溫度感測精準度。在TSMC 0.18μm標準CMOS製程中，本系統於溫度範圍-40°C～80°C操作下，每次取樣所需功率約為46nJ，且溫度感測精準度為-0.37°C～+0.29°C。

關鍵字

溫度感測器 ； 全數位校正電路 ； 環形振盪器 ； 控制單元

並列摘要

In this paper, an all digital low power temperature sensor has been developed for MEMS-based clock temperature compensation application to reduce the resonator's oscillating frequency error induced by ambient temperature variation, and to provide an accurate output clock. This temperature sensor adopts ring oscillator (RO) based temperature-to-digital code converter to convert the temperature sensitive oscillation frequency in a fixed time period and all-digital calibration. The temperature sensor consists of slope compensation and offset cancellation techniques for power consumption reduction and accuracy improvement. Based on TSMC 0.18μm standard CMOS technology, this sensing system achieves 46nJ per sample in temperature range -40°C ~ 80°C, and the inaccuracy is -0.37°C ~ +0.29°C.

並列關鍵字

Temperature Sensor (TS) ； All Digital Calibration Circuit (ADCC) ； Ring Oscillator (RO) ； Control Unit (CU)