DP83TC811S-Q1: Interface forum

Alpha Ting

Intellectual 550 points

Part Number: DP83TC811S-Q1

Hi Sir,

Now our design PHY and RJ45 are placed at two separated board.

What is the magnetics placement rule closing to either PHY or RJ45?

And what is the routing length constraint in DP83TC811S?

thanks.

Alpha

over 5 years ago

0 Vikram Sharma over 5 years ago

TI__Genius 16030 points

Hi Alpha,

For automotive phy 811 connector should be matenet connectors and not RJ45. We recommend the following because there are stringent phy level IEEE specs of mode conversion, return-loss etc and also these are helpful to meet automotive EMC/EMI requirements :

1. the connector and phy to be on the same board

2. mdi traces : matched 100 ohms differential routing

3. mdi traces : burried (if possible)

Also please refer to these app-notes for further layout guidelines :