LIN Bus Protocol – Hardware Constituents, Working and Applications

 

LIN is a sophisticated network that is now employed in the automobile industry. If we consider the former network in the automotive industry, it was full of mechanical components, but it has now been replaced by an intelligent mechatronics system.

LIN Bus Hardware

The LIN standard was created to enable for the use of very low-cost hardware nodes in a network. It is a single-wire, low-cost network based on ISO 9141. Microcontrollers with UART capabilities or specialized LIN hardware are employed in today's vehicle networking topologies.

 The microcontroller creates (partially) all LIN messages and is connected to the LIN network through a LIN transceiver (simply speaking, a level shifter with some add-ons). Working as a LIN node is merely one aspect of the capability available. This transceiver may be included in the LIN hardware and act as a pure LIN node with no additional functionality.

LIN Bus Working Principle

A LIN bus operates in a reasonably simple manner. Every LIN system is made up of one master LIN bus device and several slave devices that are linked together. Each slave has a specific duty to do, but all these duties are completely controlled by the master LIN bus device.

The message frame is the message that is sent from a LIN bus device to a slave device. It is separated into message header and message frame. Message header, which is always delivered from master to slave, consists of three separate fields: break, synchronization (Sync), and identification (ID). Likewise, the message response, which always receives the message delivered by the master node, comprises two different fields such as data and checksum.

LIN Bus Applications

Because the LIN system is mostly associated with the automotive sector, let’s have a look at its applications while managing various sections of the vehicle:

·       The vehicle ceiling: A LIN system is used on the roof of a car to operate sensors such as the sunroof sensor and the light control sensor.

·       The vehicle Seat: It is used in car seats when the position of the seat is controlled by a motor that is controlled by the LIN system. It is also used to regulate the occupant sensor and control panel sensor, both of which are situated at the seat.

·       It also helps to regulate engine sensors such as the cooling fan motor sensor and the illumination senor, which controls the lighting of light.

·       It is used on the steering wheel of a car to manage the climate control sensor, wiper sensor, turning light sensor, radio, and wheel lock sensor, among other things.

·       It is used at the car door to regulate the position of the motor that is integrated with the door mirror.

Conclusion

The LIN bus is a low-cost serial communications technology that successfully facilitates remote application within the network of an automobile. It is designed specifically for mechatronic nodes in dispersed automotive applications, although it is also suitable for industrial applications. It is designed to supplement the current CAN network, resulting in hierarchical networks within vehicles.