I'm doing some home project, and would like to use this CAN transceiver (note just in case, not selecting CAN controller+transceiver chip, that's how I need it). I would like to use this transceiver from PIC (high speed, and can get it now in DIP..) MCP2561/2FD, link to the device webpage

I want to connect 2, 3 of these, for higher speed communication for my nodes - I hope above 2Mbps (transceivers support upto 8Mbps). My nodes will be basically on different bread boards, and I'm trying to figure out simplest or most essential connection I need.

Looking at Sec. 1.8 in that reference - Typical applications. Can I just use one 5V supply for both - my MCU and the transceiver - and the bus, using the 2 120 resistors, and ignore that SPLIT line? (sort of combining those 2 cases they have into one ..). Could I skip the 0.1 uF diode, using 1 power supply / Vdd ?

Do I need LDO's at all, can't I just connect to my power supply 5V?

  • \$\begingroup\$ Do you actually want CAN FD? That's pretty unlikely for hobbyist purposes. Are you sure that you don't actually want MCP2561/2 and not MPC2561/2FD? These are different hardware layers. The former is classic "high speed CAN" and the latter is a new "higher speed yet" standard. \$\endgroup\$ – Lundin Oct 22 at 12:35
  • \$\begingroup\$ @Lundin : yes, I chose the highest rated speed wise. Want to try use fastest rated speed. Do not plan to have any other type transceiver on my bus. \$\endgroup\$ – v01d Oct 24 at 2:25
  • \$\begingroup\$ @Lundin, also, not sure if you were asking because of compatibility, but it says " .. In addition, CAN FD is compatible with existing CAN 2.0 networks, allowing the new protocol to function on the same network as classic CAN." Just in case. I didn't plan to use any non CAN FD, but this seems to suggest I would be able to. \$\endgroup\$ – v01d Oct 24 at 2:30
  • \$\begingroup\$ It is only compatible if you use the same data baudrate. If you would mix classic CAN with CAN FD and use different errors, you'll get error frames and possibly make all communication impossible, but you won't break any hardware. \$\endgroup\$ – Lundin Oct 24 at 11:13
  • \$\begingroup\$ Also what do you mean with "Do I need LDO's at all, can't I just connect to my power supply 5V?". What's your power supply? You'll need a clean, regulated voltage. \$\endgroup\$ – Lundin Oct 24 at 11:15

The specs ought to be clear in the datasheet.

 Vdd = 4.5V to 5.5V, V IO = 1.8V to 5.5V 

Use whatever you got in that range, or all 5V

  • \$\begingroup\$ Hi Tony, what about the other items? Sorry I'm not EE guy. \$\endgroup\$ – v01d Oct 20 at 3:35
  • \$\begingroup\$ As far as I see you can use 5V on all, but you can read the datasheet right? All shared with low ESR caps on each. N o need for diodes AFAIK. use the 5V R arrays then \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Oct 20 at 3:38
  • \$\begingroup\$ Optional resistor to allow communication during bus failure (CANL shorted to ground). ( Snip ) is for split \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Oct 20 at 3:42
  • \$\begingroup\$ Ok thanks Tony. I was thinking to skip Split, but it seems they say it may be needed for high rate data (if I got that right ...) \$\endgroup\$ – v01d Oct 20 at 3:52

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