DS90UB964-Q1: 964 eye diagram check

Sherry Liang

Part Number: DS90UB964-Q1

Hi team,

When the customer test the DS90UB964-Q1's eye diagram as below, and then found that the amplitude is a bit large. What's the reason? Is there an amp inside？ The eye diagram is normal? If not, could you please tell me the possible reason?

Thanks & Best Regards,

Sherry

over 6 years ago

0 Casey McCrea over 6 years ago

TI__Guru** 103215 points

Hello Sherry,

The differential amplitude does seem a bit large, but the eye diagram doesn't seem completely unreasonable. The 964 does have a CTLE inside to amplify the signal based on the adaptive equalizer. I would suggest using the MAP tool to analyze the system margin: http://www.ti.com/lit/ug/snlu243/snlu243.pdf

Best Regards,

Casey

0 Sherry Liang over 6 years ago in reply to Casey McCrea

TI__Genius 10255 points

Hi Casey,

So can we tell whether this phenomenon is normal through this eye diagram before doing the MAP analysis?

Thanks & Best Regards,

Sherry

0 Casey McCrea over 6 years ago in reply to Sherry Liang

TI__Guru** 103215 points

Hello Sherry,

I don't think there is a problem here.

Best Regards,

Casey

0 Sherry Liang over 6 years ago in reply to Casey McCrea

TI__Genius 10255 points

Hi Casey,

The eye diagram 's amplitude is large. Is there a problem with the operation, or other problems? The customer wants to know why the eye diagram's amplitude is large?

Thanks & Best Regards,

Sherry

0 Casey McCrea over 6 years ago in reply to Sherry Liang

TI__Guru** 103215 points

Hello Sherry,

I don't suspect any problem with operation, but you can verify margin performance with the MAP tool as I mentioned. I suspect that there is a measurement issue causing you to see the large amplitude actually.

Best Regards,

Casey

Interface

Interface forum

DS90UB964-Q1: 964 eye diagram check