Is a CAN Transceiver needed for a NUCLEO-F446RE?

[drtarr]

That's basically it.  I'm thrown off because this page explicitly says it has a 'CAN FD Transceiver', however, nothing says CAN on the silkscreen and this graphic I found:

 

 

Refers to the D14 and D15 pins as "CAN TD" and "CAN RD", which I assume is TX and RX implying that I would need a transceiver (CAN uses CAN High and CAN Low).

 

Am I right in understanding that I need a MCP2551 or similar transceiver despite what the product description page says?

[Andrew Neil]

Have you looked at the schematics? Is a transceiver present?

And the User Manual ?

[mƎALLEm]

Hello,

There is no CAN transceiver on NUCLEO-F446RE board. "CAN TD" and "CAN RD" are just for CAN_Tx and CAN_Rx pins of the STM32 CAN peripheral and not CAN_H and CAN_L.

If you need to use CAN in normal mode you need to add a CAN transceiver. For example as you stated MCP2551. Also SN65HVD230 is another option.

Otherwise you can use CAN in loopback mode without any transceiver and you don't need any CAN bus to be established. 

Hope that answers your question.

[Andrew Neil]

---

@mƎALLEm wrote:

There is no CAN transceiver on NUCLEO-F446RE board ... If you need to use CAN in normal mode you need to add a CAN transceiver. .

---

So the Product Page is misleading.

Also the Data Brief:

 

[mƎALLEm]

@Andrew Neil ,

DB mentions it's specific for some boards:

And it seems NUCLEO-C092RC board  has indeed a CAN transceiver: 

I think the board is not yet available on the market, but according to the image from CubeMx:

The transceiver is there:

The board status is marked as Coming soon.

[Tesla DeLorean]

A low cost diode based bench model would allow for quick evaluation in a tightly controlled environment.

https://www.keil.com/appnotes/files/apnt_236.pdf#page=4

The STM32F446 supports CAN 2.0 not FD modes

[drtarr]

Thanks for the feedback everyone - Sounds like my understanding is correct.  I do think the product page was very misleading, I actually chose this NUCLEO board just because I thought it had a transceiver, but at least I figured it out.