The Design Of Heavy Truck Tire Pressure Monitoring System Based On CAN Bus

In recent years, with the growing of automobile industry, related electronic technologydeveloping rapidly and widely used. Such as heavy truck, the traffic accidents caused hugeloss to people’s life and property safety, so people’s requirement of the safety, comfort andreliability of heavy trucks is higher and higher. And tire defect is one of the most importantreasons for the sudden traffic accidents, which is the most difficult to prevent. Tire burst isone of the most common cause of tire defect, which can lead to traffic accidents is alwayscaused by abnormal tire pressure or tire temperature is too high. So how to prevent tire bursthas become an important subject for automobile security, the key is to keep standard tirepressure and found the tire defect promptly.So how to monitor tire pressure and temperatureconditions in time is very important.In this paper, first of all analysis the current situation of TPMS, then put forward thesuitable type of TPMS is the direct two-way active type, then design the overall structure ofthe system, and divide it into different function modules, such as CAN bus module, theCAN/LIN bus module, the low frequency awakens module, TPMS modules and power supplymodule.Secondly complete the circuit design based on the function of each module. The designof CAN bus module adopts the advanced optical isolation chip6N137to isolate datatransmission, between CAN bus and ground wire joining the mine-resistant surge transientsuppression diodes, to improve the reliability and security of data transmission. In the lowfrequency awakens module adopts TC4422drive chip, and circuit inductance of LC circuitadopts winding inductance, to improve the strength of the low frequency signal. Sensors usedin TPMS modules is SP37chip, which can realized the high integration density andminiaturization of the module demand. And in the design of PCB take some rules tostrengthen the ability of anti-interference. Finally to debug and test the function, results show the CAN bus communicationfunction is good, data transmission is accurate and reliable, TPMS module realized themonitor of the tire temperature and pressure values, the wireless communication function isgood, so the system is reasonable, and realize the basic function.