Slave application for LIN transceiver
Created: Mar 05, 2014
No description available.
Local Interconnect Network or simply LIN is a serial network protocol used for communication between components in vehicles. Car industries pave ways in searching for a cheaper yet high class serial network communication devices such as LIN in exchange to CAN bus. European car manufacturers started using different serial communication topologies that led to compatibility problems.
The TJA1020 is a low power LIN transceiver used in automotive and industrial applications. It supports the single wire bus signal representation being described in the LIN protocol speciﬁcation for in-vehicle Class-A buses with a single master node and a set of slave nodes. Local Interconnect Network (LIN) is a serial bus protocol being primarily intended for transmission of control related data between numbers of bus nodes.
The protocol controller (e.g. microcontroller) is connected to the LIN transceiver via a UART/SCI based interface or standard I/O port pins. The TXD pin of the TJA1020 is the transmit data input and the RXD pin is the receive data output. A microcontroller port pin can control the sleep control input NSLP of the LIN transceiver. The TJA1020 provides an internal slave termination resistor. Thus for a slave application, no extra LIN bus termination resistor is needed. The capacitor CSLAVE is recommended in order to improve the EME as well as EMI performance of the LIN system. In mixed-supplied LIN networks, where the supply of some slave nodes are ignition key controlled while others are permanently connected to battery, unsupplied slave nodes represent pull-down loads on the LIN bus. Thus, it is recommended to apply the trimmed master termination. With the trimmed master termination the pull-up during Sleep mode RMASTER-BAT can be adapted to the pull-down behavior of unsupplied slaves.