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I am currently communicating between two microcontrollers using a single pin and the LIN protocol over a short distance of 0.2m. Now I would like to extend the distance up to 5m by differentially driving the communication (using a RS485 or 232 transceiver etc.). It is not possible to change any aspect of the current design so I am thinking of attaching a PCB to the microcontrollers at each end and communicate between the PCBs differentially. Is anything like the attached image possible? The difficulty I am having is in splitting the signal from single to differential as most transceivers require an Rx and Tx. This would be fine If I could split the signal before the transceiver. enter image description here

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    \$\begingroup\$ LIN is a common bus system in modern cars. The bus lenght can easily reach 5m without any problems. Do you have a LIN transceiver between your uC and LIN bus? It will handle the transmission voltage levels and ensure a clean communication. \$\endgroup\$ – A.R.C. Dec 5 '18 at 10:42
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LIN is very slow protocol (20,000 bits per second) with controlled slew.

Just run a twisted pair (signal, return) between the two transceivers.

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  • \$\begingroup\$ The difficulty comes from converting from single line to a double line and then back again. I'd effectively like to go from LIN to RS485 and back to LIN. Any suggestions on how that could be achieved? \$\endgroup\$ – ChrisD91 Nov 15 '18 at 7:34
  • \$\begingroup\$ LIN is very slow, and tolerant of large capacitances. Why must you use RS485? \$\endgroup\$ – analogsystemsrf Nov 16 '18 at 3:10
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LIN Spec 2.2A, Table 6.11 specifies the maximum length of the bus line as 40 meters. Converting to a differential signal for 5 meters won't achieve any extra reliability.

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