DP83867IR: Crystal input frequencies

Ryan Thompson31

Part Number: DP83867IR

Hi,

Can the DP83867IR run on frequencies other than 25MHz on the crystal oscillator input? If not are there any Ethernet 1000Base PHYs from TI that can accept other frequencies like 50MHz or 125MHz? (EMI concerns).

over 8 years ago

0 Rob Rodrigues over 8 years ago

TI__Mastermind 19780 points

Hi Ryan,

The DP83867 only accepts 25 MHz as a reference clock. TI does not have a 1000base-t PHY that accepts anything other than 25 MHz as a valid reference clock.

What EMI concerns do you have with 25 MHz?

Best Regards,

0 Ryan Thompson31 over 8 years ago in reply to Rob Rodrigues

Prodigy 20 points

Hi Rob,

Thanks for your fast reply. For a design I'm working on the harmonics (although weak relatively speaking) from 25MHz crystals/clocks cause problems with a particular component I'm stuck with.

0 Rob Rodrigues over 8 years ago in reply to Ryan Thompson31

TI__Mastermind 19780 points

Hi Ryan,

That is unfortunate. Again, we don't have any options other than 25 MHz devices and you'll have to use PCB techniques to mitigate the 25 MHz on other places of the board.

Best Regards,

Interface

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DP83867IR: Crystal input frequencies