Ethernet - Connect 2 PHY on one PCB Directly

[AWeirdo]

Hi, NXP Community!

Due to some cost considerations, I need to change the 2-box solution of the previous mass production plan to a 1-box solution at the hardware level.

In the previous two boxes,

the SoC of one Box was connected to a NXP TJA1103A PHY,

and the SOC of the other Box was connected to a Marvell 88Q5040 Ethernet Switch.

And There are two Ethernet Connectors connected to them respectively, then use the 100MBase-T1 to realize the Ethernet communication between two boxes.

For the need to integrate these two box into one box,

Is it possible to connect the NXP TJA1103A PHY and the Marvell 88Q5040 Ethernet Switch directly on the One box Chip, to cancel the two Ethernet Connectors and 100MBase-T1 Cable, and realize the Ethernet communication between 2 SoCs on one Chip?

I'm looking forward to your reply,

I will appreciate it!

Hope everything goes well around you!

Yours

Vincent

[PavelL]

Hello @AWeirdo ,

I apologize for the delayed response due to public holidays.

Yes, from a theoretical standpoint, it is possible to connect the NXP TJA1103A PHY and the Marvell 88Q5040 Ethernet Switch directly on a single PCB.

However, in a single-board design, using a PHY like the TJA1103A is unnecessary and overly complex. The PHY is designed for physical layer transmission over cables, which is not needed when all components are integrated on the same board.

Since a redesign is already being planned, the most efficient and logical approach would be to connect the SoC (or MCU) directly to the Marvell 88Q5040 switch using a digital interface such as RGMII, SGMII, or MII - depending on what is supported by both the SoC and the switch.

Using a PHY in this context would be overkill – like using a sledgehammer to crack a nut.

I would not recommend using a PHY in such a setup.

Best regards,

Pavel