Characteristics and Applications of LIN Bus Topology

The LIN bus is a serial communication protocol used in automotive electronic systems that offers several significant advantages. First of all, it uses serial communication, which effectively reduces inter-line interference, saves wiring harness resources, and can achieve longer transmission distances. Secondly, the LIN bus adopts a single-wire transmission mode, which enhances the compatibility of the ISO9141 standard, and the bus voltage is based on VBAT. In addition, its maximum transmission rate is 20Kbit/s, which is enough to meet the needs of most applications on the car body. The LIN bus also adopts a single master and multiple slave structure without arbitration. Based on the universal UART/SCI interface, almost all MCUs have the hardware foundation of the LIN bus. Slave nodes do not require a crystal or ceramic oscillator to achieve synchronization, significantly reducing costs. A bus can connect up to 16 nodes, determined by the electrical characteristics of the bus. Finally, the LIN bus also supports diagnostic functions, including UDS services.