AN1278 Datasheet, PDF (1/44 Pages) STMicroelectronics – Many mechanical components in the automotive sector have been replaced

AN1278
APPLICATION NOTE
LIN (LOCAL INTERCONNECT NETWORK) SOLUTIONS
by Microcontroller Division Applications
INTRODUCTION
Many mechanical components in the automotive sector have been replaced or are now being
replaced by intelligent mechatronical systems. A lot of wires are needed to connect these
components. To reduce the amount of wires and to handle communications between these
systems, many car manufacturers have created different bus systems that are incompatible
with each other.
In order to have a standard sub-bus, car manufacturers in Europe have formed a consortium
to define a new communications standard for the automotive sector. The new bus, called LIN
bus, was invented to be used in simple switching applications like car seats, door locks, sun
roofs, rain sensors, mirrors and so on.
The LIN bus is a sub-bus system based on a serial communications protocol. The bus is a
single master / multiple slave bus that uses a single wire to transmit data.
To reduce costs, components can be driven without crystal or ceramic resonators. Time syn-
chronization permits the correct transmission and reception of data. The system is based on a
UART / SCI hardware interface that is common to most microcontrollers.
The bus detects defective nodes in the network. Data checksum and parity check guarantee
safety and error detection.
As a long-standing partner to the automotive industry, STMicroelectronics offers a complete
range of LIN silicon products: slave and master LIN microcontrollers covering the protocol
handler part and LIN transceivers for the physical line interface. For a quick start with LIN,
STMicroelectronics supports you with LIN software enabling you to rapidly set up your first LIN
communication and focus on your specific application requirements.
Figure 1. LIN Network Overview
CAN Bus ^MASTER
LIN Bus
SLAVE
SLAVE
SLAVE
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