TLK3131ZWQ

WhiteHorse

Support,

Our customer is reviewing their schematics and a question has come up regarding the TLK3131ZWQ and unused RXD pins. THey use the part in RGMII mode and therefore only use the RXD(3:0) pins. Do they need to terminate the unused RXD(7:4) pins?

Thanks for your help.

Regards,

John Wiemeyer

over 11 years ago

0 Michael Peffers over 11 years ago

TI__Mastermind 20820 points

Hi John,

It is good to force these pins into a known state to reduce the amount of noise that couples into the systems.

Regards,

Michael Peffers

Analog Applications Engineer

0 WhiteHorse over 11 years ago in reply to Michael Peffers

Genius 4430 points

Hi Michael,

There are several modes for these pins, but they are always defined as ouputs in the data sheet. If they truly are always outputs then they should always be at a known state. The question is would there be a time when they are not driven?

Regards,

John Wiemeyer

0 Michael Peffers over 11 years ago in reply to WhiteHorse

TI__Mastermind 20820 points

HI John,

You are correct, I got my wires crossed on Tx and RX. The Tx side you typically would terminate to protect against noise but the Rx pins you can leave floating.

Regards,

Michael Peffers

Analog Applications

0 WhiteHorse over 11 years ago in reply to Michael Peffers

Genius 4430 points

Thanks Michael!

Regards,

John Wiemeyer

Interface

Interface forum

TLK3131ZWQ