一种适用于RFID标签的高精度温度传感器的分析与设计

摘要

论文描述了一种集成于RFID标签芯片的高精度CMOS温度传感器,该温度传感器采用SMIC 0.18μm 2P4M CMOS工艺.利用MOS管工作在亚阈值区域时的温度特性,产生与绝对温度成正比(PTAT)的电流,替代了传统的BJT.电流控制振荡器(CCO)将PTAT电流转换成频率与温度成正比的时钟信号,该时钟信号通过计数器转换为数字信号.通过对电流源和比较器的优化设计,该温度传感器在温度范围为-20℃～50℃时误差仅为-o.1/+0.3℃.电源电压为1.8V时,工作电流小于50μA.%This paper describes an ultra-high accuracy CMOS temperature sensor intended for RFID applications, which is implemented in SMIC 0. 18μm CMOS process. Instead of using any bipolar transistor, the proportion to absolute temperature(PTAT) current generator is based on sub-threshold MOS operation. A current-controlled oscillator(CCO) can be utilized to transform the PTAT current into temperature-dependent clock signal which is converted into digital signals by a counter. Through the optimization of the design of the current source and comparator, the sensor achieves a sensing inaccuracy of -0. 1/ + 0. 3℃ over operating temperature range from - 20℃ to 50℃, which consumes less than 50μA from a 1. 8V supply.