UCC28070: PMP4311 schematic and BOM

CCphi CCsora

Intellectual 540 points

Part Number: UCC28070

We are designing Interleave PFC with UCC28070 follow the ref. design PMP4311.

We downloaded BOM and schematic from this link. http://www.ti.com/tool/pmp4311

But we found that the material value in schematic & BOM are different.

Example : =

C38, C39, C47,C48 : value in schematic is 4700pF but value in BOM is 1000pF.

C66 : value in schematic is 220uF but value in BOM is 1000uF.

So, which one is the correct one ? Should we follow value in schematic or value in BOM ? or Does it have any new version of PMP4311 's schematic & BOM ? Thank you.

over 8 years ago

0 Peter Meaney over 8 years ago

TI__Mastermind 31580 points

Hi

I have asked the original designer to clarify the discrepancy.

Regards

Peter

0 CCphi CCsora over 8 years ago in reply to Peter Meaney

Intellectual 540 points

Hi Peter,
Did you get reply from original designer yet ? Kindly please help to update.

Thank a lot.
CCphi

0 John Griffin1 over 8 years ago in reply to CCphi CCsora

TI__Mastermind 34465 points

Hello CCphi,
I am not the designer of this reference design but perhaps I can help.
The value of C38,39,47 and 48 is determined by the overall system EMI test results of pfc and post regulator stages. Factors such as pcb layout and packaging play a large factor in the final value chosen. As a "place holder" I suggest that you plan on using a value of 4700pF. The final value is determined by the EMI emission results and requirements.
Use 1000uF for C66.
Sorry about the discrepancies between schematic and BOM. This should have not occurred.

Regards
John

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UCC28070: PMP4311 schematic and BOM