DS90UB936-Q1: pseudo-differential signal traces under COAX mode

Sherry Liang

Part Number: DS90UB936-Q1

Dear team,

Below is 936's RIN trace, and they use COAX cable. They use pseudo-differential signal traces here in order to reduce common mode noise. They have two questions here,

1. Can we use the pseudo-differential signal traces under COAX mode?

2. If it is ok to use pseudo-differential signal traces, then how do we set the characteristic impedance of pseudo-differential signal traces, 50ohm or 100ohm?

Thanks & Best Regards,

Sherry

over 3 years ago

0 Logan Cummins over 3 years ago

TI__Guru 63270 points

Hi Sherry,

Thanks for your question. I'm looking into this and will get back to you soon.

Regards,

Logan

0 Logan Cummins over 3 years ago in reply to Logan Cummins

TI__Guru 63270 points

Hi Sherry,

It's typically recommended to loosely couple the RIN+/RIN- traces, making the spacing greater than 3x the width of the trace. Given the COAX and single-ended to the termination, 50 ohm termination is required.