How to handle TVDD pin

[upartners]

In LS1043ARDB, the Pin TVDD(V6) is connected to +TVDD, in our products, we remove the ETHERNET_PHY_10G and do not use any 10G PHY module,the board work without 10G ethnet. We also expect to removing +TVDD power supply chip is U17.
But we do not know how to handle those pins：TVDD(V6),EMI2_MDC(Y6)，EMI2_MDIO(W6). Could you please give me some suggestions of handling those pins?

Looking forward to your reply.

Have a great day.

[alexander_yakov · Accepted solution]

According to "LS1043A Design Checklist" (application note AN5012), Table 4, TVDD "must remain powered" if not used.

EMI2_MDC and EMI2_MDIO pins must be tied low through a 2-10 kΩ resistor to ground (GND), or these pins may be configured as a a GPIO and output, and than left floating - this is said in Table 25.

Have a great day,
Alexander

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[upartners]

Thanks.

I have understood.

Can we tie the TVDD to +1.8V power which supplied by PMIC(U33)? If we can, we can remove the U17.

Looking forward to your reply.

Have a great day.

[alexander_yakov]

If TVDD is not used, you can tie it to any voltage source from the list of supported voltages: 1.2 V, 1.8 V or 2.5 V

Note that even if TVDD is not used, recommended power sequencing for this voltage input must be met.

Please look LS1043A Data Sheet, Section 3.2 "Power sequencing"