DP83TC812EVM-MC: 100Base-T1 signal test

Hi,

I would suggest probing the 100Base-T1 signal using a differential probe across the TRD_M and TRD_P pins. 

The signal should look like the yellow signal below at link up. 

Best regards,

Melissa

Hi I want to see   the   signal  details， could you please  Stretch the  timeline ？ 

Hi,

Why do you want to see the signal details? What is this for? Are you seeing an issue with the TI DP83TC812EVM?

Best regards,

Melissa

my  test result is poor， I want to  see  your  test result  as a compare，  I am not sure  the signal   I test whether is ok

Hi,

Please confirm you are using a differential probe and measuring it across the connector output of the TRD_P and TRD_M pins.

If you do not have a differential probe, you may use a single ended probe to measure TRD_P to GND in channel 1 and TRD_M to GND in channel 1 and perform a MATH function on the scope and do Channel1-Channel2.

Best regards,

Melissa

I measured it the way you said， wiht 3.5GHz  bandwidth    differential probe。 I want to  the signal  detail   you test   as  a contrast， wil you  provide it？ thank you！

hi   

1.The expected waveform is shown above------ I can‘t see ’the TRD_P A&TRD_N  details，

2.Can you provide a photo of your waveform?---------A:  I has put my  waveform below my qustion  at  the begginning.

3.Are you trying to measure the waveform for compliance? What is your application?---- I am testing the EVM board‘s’  TRD_PP&TRD_N  signal  Quality ,  I plan to  use  the PHY chip  for  our  new  design,  I should  make  sure this  PHY  chip  is no problem； I don't thik  there is  any issue   in the EVM ，I just want to see  the  RD_PP&TRD_N  signal  details  as  a contrast.

Hi,

Im a little confused on what specific derails you require. The amplitude? The scale is shown in the photo if needed.

Are you measuring the signal at linkup? Can you provide a photo of your probe?

Best regards,

Melissa