LIN interface
The LIN interface is electrically isolated from the other interfaces of the module and also protected against overload or misuse.
Operating modes
The four clients of the LIN interfaces (see chapter “Multi-Client Support”) can either be operated in the LIN master operating mode or in the LIN slave operating mode. The following configurations are possible:
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Client 1: LIN master or LIN slave
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Client 2 - 4: LIN slave
The operating mode is selected in the application software.
Voltage supply on the LIN bus
12 V LIN systems
In 12 V LIN systems, the LIN nodes of the ES134.1 module can either be supplied externally by the LIN bus or internally by the module with the LIN reference voltage VBAT.
24 V LIN systems
In 24 V LIN systems, the LIN node of the ES134.1 module can only be supplied externally by the LIN bus with the LIN reference voltage VBAT.
Supplying external LIN nodes
The module is not designed for the supply of external nodes on the LIN bus.
Selecting the voltage supply
An internal pull-up resistance can be switched to the LIN interface of the module as master resistance. Switching of the master resistance of the LIN interface can be configured in the application software.
Recommendation
To maintain the reference level (and thereby identical switching thresholds) at the individual nodes on the LIN bus, the LIN transceivers (physical layer) of all nodes on the bus should be operated with the same voltage.
We therefore recommend powering all nodes on the LIN bus with the external voltage that also powers the other bus participants (LIN VBAT).
At the same time, this ensures compliance with safe switching thresholds in each operating state of the LIN system (e.g. during vehicle cold starts).
If there is no access or no possibility of using the LIN VBAT voltage as reference and supply voltage, the LIN transceivers of the dedicated LIN node of the ES134.1 can be supplied by a switchable internal voltage source of the module.
This internal supply voltage is not routed outside via the LIN plug connector.