Connection between the Ethernet transmitter and the Ethernet switch on the same board?

Hello everyone,

I am working on a project that involves an Ethernet Switch (RTL8305NB-VB-CG) and an Ethernet Transceiver (LAN8720A). They will be connected on a single PCB. Does anyone know if it is mandatory to use isolation transformers (for TX, RX), or is it not required since they are on the same PCB? I would be grateful if someone could provide a correct connection schematic.

I am not 100% sure, but some application notes suggest that isolation capacitors for each line are sufficient if they are on the same PCB. I am connecting them this way(attached screenshot), but I want to be completely sure.

I will be happy to any help!😊

My references:

Capacitive Coupling Ethernet Transceivers without Using Transformers (microchip.com )

AN-1519 DP83848 PHYTER® Transformerless Ethernet Operation (Rev. A)

Tuning the 8255x Controller’s Equalizer Application Note 435 (intel.com )

https://www.ti.com/lit/an/slla310/slla310.pdf?ts=1719011312654

https://www.analog.com/media/en/technical-documentation/application-notes/ee-269.pdf

https://ww1.microchip.com/downloads/en/Appnotes/VPPD-01534.pdf

[second screenshot]

Thank you.

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