Local interconnect network (LIN)

Local Interconnect network (LIN) is a 1-wire interface used in automobiles mainly intended for diagnostics implementation. LIN is a serial interface used as a replacement for costly and feature rich CAN interface. LIN is a robust communication protocol which supports automotive environments. LIN basically can be said like a inter-chip communication. The slaves can be daisy chained or connected in shunt.

LIN supports master-slave configuration as like other serial protocols and protocol can address up to 16 slaves. LIN is mainly an automotive protocol also intended for usage in industrial applications. Check any microcontroller supporting automotive applications, you will find LIN interface.

LIN supports a hierarchical node structure where data is transferred between nodes in a fixed format. The master sends the synch data and identification fields to which corresponding slave responds.

To connect microcontroller to network using LIN, a LIN transceiver is required. This is in similar lines to uart communication. For internal communication within an automotive application, LIN interface is preferred.  At the broader level, CAN is used for communication.

Specifications of LIN:

• ·         Single master, 16 slaves
• ·         No bus arbitration as like I2C
• ·         Speed up to 19.2kbps
• ·         Maximum bus  length supported is 40m
• ·         Half-duplex communication
• ·         2-byte, 4-byte, 8-byte frames
• ·         Error detection mechanism

What are advantages of LIN?

• ·         Simple interface
• ·         Low cost and efficient in implementation