基于CAN总线通信的程控电阻系统设计

Programmable resistor system design based on CAN bus communication

由于电阻信号良好的抗干扰性和渐变特性,电阻式传感器被广泛使用到了汽车上,如燃油传感器、水温传感器,空调温度传感器等等.车载ECU在进行功能、电性能及网络台架测试阶段,其电阻输入信号需要在限值范围内动态模拟.传统的动态电阻模拟是手动切换固值电阻的接入,这样不仅无法发挥电阻式传感器的渐变特性,而且给操作带来了极大的不便.市面上也有类似的程控电阻产品,但是由于电阻值范围以及与汽车网络兼容性的限制,无法在汽车电子电器自动化测试中发挥应有的作用.针对这一问题,本文提出了一种基于CAN总线通信的程控电阻板卡设计.文中详细介绍了该程控电阻系统的设计原理,并对其技术性能进行了详细的分析.通过对燃油传感器的实际测试,该系统可满足汽车电子电器自动化测试的要求.

Resistive sensors are widely used in automobile due to good anti-interference and gradient features. The input resistance signal needs dynamic simulation within limits during the bench testing phase of automobile ECU in function, electric properties and network. Traditional resistance dynamic simulation is to switch the connection of fixed resistance manually, this not only makes the resistance fail to play the gradient feature, but also brings great inconvenience to oper- ation. Although there are similar programmable resistance products on the market, but due to the constraints ofresistance value range and network compatibility with the automobile, they can＇t work in the electronic automated testing of the automobile. In order to overcome this problem, a programmable resistance board design based on CAN bus communication is put forward in this paper. The design principle and its technical performance of the programmable resistor system are detailed. Through practical test of fuel sensor, the system can meet the requirements of the automation test of the automotive electrical and electronic appliances.