基于CAV424的电容式汽车油位传感器测量系统

Measure System of Capacitive Gasoline Level Sensor Based on CAV424

提出了一种基于CAV424的电容式油位传感器测量系统,该测量系统可以应用于轿车油箱内油位的检测。将由油位变化引起的电容变化量转化成电压信号,经AM402转化成4～20mA直流电流。系统同时引入PIC单片机对温度实时监测并产生相应的PWM调制脉冲信号,经滤波后作用于CAV424的参考电流源,实现对输出信号的补偿。实验证明该测量系统动态响应快,测量精度高,并且抑制温漂的效果好。

This paper puts forward a measure system of capacitive gasoline level sensor based on CAV424,which can be ap- plied in inspecting gasoline level in oil tanks.The capacitance change caused by the change of gasoline level is trans- formed into voltage signal and AM402 is transmitted into 4-20 mA DC.The system also introduces PIC single chip into re- al-time temperature inspection and therefore produces PWM modulating pulse signals which act on CAV 424 reference current supply through filtration,and achieves outcoming signal compensation.