基于MC9S12G128的CAN总线汽车组合开关的电子设计

Electronic Design of CAN Bus Automobile Combination Switch Based on MC9S12G128

为了解决传统硬线组合开关存在的信号采样不匹配和线束繁杂的问题,提出了以NXP的MC9S12G128芯片为核心,以CAN通信方式进行传输信号的组合开关电子设计方法。设计的组合开关满足UDS诊断、网络管理、Bootloader、电磁兼容性等规范要求,同时具有高低压保护功能。通过优化输入信号接口电路和软件消抖时间,消除对信号的误判。在硬件上采用以UJA1076芯片为核心的电源电路和CAN信号收发电路来减小组合开关休眠时的静态电流。实验和测试结果表明,该组合开关设计能够满足各项要求,在车用组合开关中具有较好的应用价值。

In order to solve the problems of signal sampling mismatch and complex wiring harness in traditional hard wire combination switch, the electronic design method of combination switch is put forward, which is based on the MC9 S12 G128 chip of NXP water supply and transmits signal through highspeed CAN communication. The combination switch can meet the requirements of UDS diagnosis, network management, Bootloader, electromagnetic compatibility and other specifications. At the same time, it has the function of high and low voltage protection. By optimizing the signal interface circuit and software buffeting time, misjudgment can be eliminated. The power supply and CAN signal circuit based on UJA1076 chip are used to reduce the static current of the combination switch in sleep mode. The experimental and test results show that the design of the combination switch can meet the requirements and has great application value in the vehicle combination switch.