应用于MEMS基频率源的CMOS温度传感器

A CMOS temperature sensor for MEMS-based frequency source

基于TSMC 0.18μm 1P6M CMOS工艺设计了用于在片测温的CMOS温度传感器.该温度传感器采用双极型晶体管为测温核心器件,使用缩放式模数转换器(ZOOM ADC)来实现温度信息的读取.温度前端电路采用动态匹配技术(DEM)和斩波技术来降低电流源失配和运放失调,实现对电流增益βF的补偿,提高电路的精度.同时,将ADC所需的控制时钟电路集成在片内,降低了系统应用的复杂度,整个系统面积为780μm×800μm.仿真表明,在1.8 V电源电压下电路的静态功耗为240μW,通过两点拟合校正后,实现了在-55℃~125℃量程内的测温精度为±0.5℃.

A CMOS temperature sensor for monitoring on-chip temperature based on TSMC 0.18μm CMOS IC process is presented.This temperature sensor adopts the bipolar transistors as the core device,and a zoom analog-to-digital converter(ZOOM ADC)to read temperature information.Temperature front-end circuit adopts dynamically element matched(DEM)and chopping technologies to reduce the mismatches of these current source and the offsets of the operational amplifiers.With these technologies,the current gainβF of BJT is compensated,and the accuracy of circuit is improved.The control clock circuit of the ADC is integrated in the circuit to simplify system application.This sensor occupied an area of 780μm×800μm.Simulation shown that this chip’s static power was 240μW under 1.8 V supply voltage.With 2-point fitting,sensor achieves±0.5℃accuracy in the range of-55℃to 125℃.