TPS54531: Thermal Vias filled or not filled?

Dimitri Georgaras

Part Number: TPS54531

Tool/software:

Hello,

Should the thermal vias for this design be filled or not filled?

I have seen some thermal vias on power pads which have a custom solder stencil which does around the vias. This footprint specifies the solder stencil over the thermal vias. Does this not allow solder to be wicked into the via?

I am hoping to avoid having to fill the vias to save cost on the PCB fabrication.

Thanks,

Dimitri

7 months ago

0 Andy Chen 7 months ago

TI__Mastermind 34625 points

Hi,

Vias on power pad is very helpful for better thermal performance on multi layers PCB, however the via on power pad is not allowed in some customers just because of design rule. so we strongly suggested to place vias as recommended on data sheet.

0 Dimitri Georgaras 7 months ago in reply to Andy Chen

Prodigy 20 points

Hi Andy, thank you for your reply.

My initial question is not asking about the importance of the thermal via, but whether or not the via should be filled with epoxy to prevent solder wicking from the underside of the via?

+1 Daniel Li14 7 months ago in reply to Dimitri Georgaras

TI__Mastermind 27470 points

If the bottom side of thermal via have pads close to it , then we suggest to filled with epoxy. If there is no any component nearby the thermal via in the opposite side, then you can leave it not filled.

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TPS54531: Thermal Vias filled or not filled?