DS90UB954-Q1: Placement of CMC and AC caps

Tomoaki Yoshida91

Genius 5255 points

Part Number: DS90UB954-Q1

Hi team,

I have a question for placement of CMC and AC caps.

I understand that TI recommend CMC is close connector and AC caps are close 954.

Is it okay to swap CMC and AC caps, that is, to place the CMC near the IC and AC caps near the connector?

Best regards,

Tomoaki Yoshida

over 6 years ago

0 Tomoaki Yoshida91 over 6 years ago

Genius 5255 points

Hi team,

I attached image.

Please check this.

Best regards,

Tomoaki Yoshida

0 Tomoaki Yoshida91 over 6 years ago

Genius 5255 points

Hi team,

I attached image.

Please check this.

Best regards,

Tomoaki Yoshida

0 Steven(Shenzhen) Shi over 6 years ago in reply to Tomoaki Yoshida91

TI__Mastermind 30515 points

HI Yoshida,

both solution is ok. But in figure (2), if the distance between CMC anad UB954's RIN+/- is longer (such as >3inches), it would impact the high speed serial link common-mode noise rejection, so this is not preferred/better solution.

regards,

Steven

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DS90UB954-Q1: Placement of CMC and AC caps