基于FPGA内部自激振荡与温度相关性的温度传感器

Temperature sensor based on relativity between self-oscillation in FPGA and temperature

温度是IMU及其他导航器件等精密仪器中需要监测的重要参数,传统的温度监测一般使用热电偶或者数字温度传感器(如DS18B20)等,监测程序复杂,功耗高,因此使用精密仪器中广泛采用的FPGA芯片独立完成高集成度、低功耗温度监测具有重要意义。在FPGA中通过搭建环形振荡器产生了自激振荡信号,该信号周期与FPGA芯片温度具有正相关性,通过对振荡信号周期的检测完成了对温度的监测,设计了一种以FPGA芯片同时作为敏感头和处理模块的温度传感器。通过对Xilinx Virtex-2系列FPGA芯片进行实验,得到该传感器在-40℃^+60℃的范围内具有优于0.1℃的分辨率,优于0.5℃的检测精度,满足一般温度监测需要。实验表明该传感器具有功耗低、集成度高、可靠性好等优点。

Temperature is an important parameter that needs to be monitored in IMU and other navigation devices. Thermocouple or digital temperature sensor（such as DS18B20） is usually used in temperature detecting, so a highly integrated and low-cost temperature detecting design in FPGA is important. In this paper, the self-oscillation signal was generated by ring oscillator set up in FPGA and its period had positive relativity with the FPGA＇s temperature, so the temperature could be gotten by detecting the period of self-oscillation signal. In the end, a temperature sensor using FPGA as both sensing part and processing part was designed. Experiments on the FPGA chip of series Virtex-2 from Xilinx show that the resolution is better than 0.1℃ and the accuracy is better than 0.5℃ within -40℃-＋60℃, which can satisfy the general requirement in monitoring temperature. The temperature sensor is low-cost, highly integrated and highly reliable.