DS90UB935-Q1: GPS band EMI failed(1.5GHz)

Roy Chou1

Part Number: DS90UB935-Q1
Other Parts Discussed in Thread: DS90UB954-Q1

Hi Team,

May you let me know if we met the EMI issue(relate to forward channel) in GPS band, do we have related application note that can fix it?

Or can you share common solution for it? Thank you.

Regards,

Roy

over 2 years ago

0 Hamzeh Jaradat over 2 years ago

TI__Guru** 108430 points

Hello Roy,

Are you able to locate whether the interference is coming from the board or the cable? Have you properly shielded the box?

System level EMI and EMC are very dependent on PCB design, connector cable, shielding and grounding techniques.
For mitigation without changing PCB structure you can adjust DS90UB954-Q1 REFCLK frequency to 24 MHz or 26 MHz to shift any frequency related spectrum. Alternately you can apply SSC at REFCLK input of 25 MHz +/- 0.5%. This will introduce spread spectrum on back channel and forward channel.

Additionally, please have a look into the following two Threads.

(+) Compiler/DS90UB954-Q1: ds90ub953-q1 and ds90ub954-q1 RF noise effect GPS - Interface forum - Interface - TI E2E support forums

(+) DS90UB953-Q1: Noise Reduction Methods - Interface forum - Interface - TI E2E support forums