脉宽调制输出的集成真空度传感器

An Integrated Vacuum Sensor with Pulse-Width-Modulated Output

本文提出一种优于模拟量输出的数字化传感器.由温度敏感级、加热级和施密特触发器与在加热级和温敏级间的衬底热通路一起构成一个闭环传感器系统.该系统工作在加热和冷却的振荡状态,产生方波输出,其脉宽用作为真空度的量度.该传感器由通用的CMOS技术制备,本文给出了不同真空度下的理论分析与实验结果.

A digital sensor superior to the sensor with analogical output has been proposed. It is the integrated vacuum sensor with pulse-width modulated output. It is composed of temperature sensing stage, heating stage, and Schmitt trigger. The three parts and the substrate thermal path construct a closed-loop sensor system. The sensor is fabricated by the conventional CMOS technology. It has been measured in the range of vacuum 10^(-2)～760×1. 33× 10~2 Pa and its output changes from 6. 5 ms to 11. 8 ms (high electric level).