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Bermell , 08-29-2022, 09:59 AM

Hello,

I would appreciate it if you could help me with the following question:

For a 12 layers PCB, would it be possible to route the signals corresponding to ethernet, usb, sd or emmc, under the ADP5052 component ( voltage regulators ) ?

I understand that for critical signals it would be necessary to try being far from a component as noisy as the DCDC that supplies all the voltages of the card. However, in this case, it is a board with a high component density.

I wait for your answer. Thank you very much in advance

qdrives , 08-29-2022, 02:55 PM

I would not do it.
SMPS switch at low frequencies so shielding does not work well due to the (lack of) skin effect.
Noise will pass three Gnd layers (of 1oz each).

robertferanec , 08-30-2022, 04:45 AM

I would try to improve placement.

PS: If there is no other way, it can be done (I have designed some boards where I had to route high speed signals under switching power supplies), but ideally you would like to avoid this.