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nr Bundaberg, Australia
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As some will know I am working on a new Due-style board, it will have both the SAM's CAN ports broken out to transceivers with the current circuit being as follows.



Are there any CAN experts here that can comment on this and/or suggest modifications?

NUP2202W1 is an ESD protection device.

MCP4242 is a digital pot, I may use that instead of the resistors to set the slew rate.

______
Rob
« Last Edit: May 16, 2013, 11:02:31 am by Graynomad » Logged

Rob Gray aka the GRAYnomad www.robgray.com

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That design seems very complete and correct as far as I can tell.
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nr Bundaberg, Australia
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Thanks Collin80, I think I did my due diligence with the design but I've never used CAN so it makes sense to ask those that have.

Mind you the same applies to just about everything on this board smiley

I've replaced the RS resistors with two digital pots, mostly because I was desperate for some more CPU pins and doing that freed up 4 of them.

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Rob
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Nice job Rob!
May be this is a silly question but could you tell me how the 120 ohm terminal resistors are set up?

Thank you,
Wilfredo
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Well to be honest I'm just mimicking a common circuit, obviously 2x 60R == 1x 120R and I assume the cap helps to shunt AC noise to GND.

BTW the schematics and initial PCB component placement are just about finished. We will probably freeze the design in a day or two then I'll start laying the tracks.


_____
Rob

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