Fiber optic transceiver not working with STM32H743VIt6?

[Akash_k]

I want to transmit data over fiber optic from STM32H743VIT6. I am using internal MAC of STM32H743VIT6 and LAN8742 as PHY. The ethernet signals after LAN8742 are going both in the RJ45 connector and also in Fiber optic transceiver. I am using AFBR5803ATQZ as fiber optic transceiver. Ethernet is not working using AFBR5803ATQZ as fiber optic transceiver.

[LCE]

So the ethernet signals go to the RJ45 connector (hopefully with internal transformer and termination) and the optical transceiver?

That might be a) a little bit too much for the LAN chip, and / or b) layout / PCB routing might create some problems here.

And is that optical transceiver really IO compatible to the LAN chip?

[Akash_k]

So the ethernet signals go to the RJ45 connector (hopefully with internal transformer and termination) and the optical transceiver? Yes

And is that optical transceiver really IO compatible to the LAN chip? Is there any special PHY required for optical transceivers or PHY for ethernet will work for Optical transceiver as well.

[Akash_k]

So the ethernet signals go to the RJ45 connector (hopefully with internal transformer and termination) and the optical transceiver? Yes

And is that optical transceiver really IO compatible to the LAN chip? Is there any special PHY required for optical transceivers or PHY for ethernet will work for Optical transceiver as well.

[LCE]

Check the datasheets for required signal levels...

But usually the ethernet-PHY has to drive a transformer, which is rather injecting currents, so you might have a problem there.

In case of doubt -> oscilloscope.

But I'd rather be surprised if that works without some extra circuitry.

[Piranha]

PHY chips with fiber support are different and manufacturers note that capability explicitly. Those chips have special fiber modes and configuration. For a complete example even with your specific transceiver, look here:

https://www.ti.com/tool/TIDA-00928

[JArig.1]

Hello, did you manage to solve the issue? I would like as well to use ethernet with a fiber optic transceiver using the LAN8742.

Thanks

[Piranha]

And I want a flying bicycle... Why are you incapable of opening a Microchip web-page and reading that LAN8742 is for wired Ethernet only?

[Pavel A.]

Please, don't fight