LMZ31710: PCB layout and stress question

Ruixin Feng

Part Number: LMZ31710

Hi Team,

On customer PCB, LM31710 is very close to a screw hole. The diameter of screw hole is 3.5mm. The distance from the edge of module to the center of screw hole is 5.5mm. Customer concerned about the stress issue. So I was wondering if there is any restriction about the distance between module and screws. Could you pls give some comments on it? Thanks!

Rayna

over 2 years ago

0 Tahar Allag over 2 years ago

TI__Mastermind 32420 points

Hello Ruixin Feng,

There is no restrictions as long as it is not effecting the device from electrical performance.

If the Board will be exposed to lots of thermal cycling over its life time, we recommend doing BLR (Board level Reliably) testing and see how the board mechanical movement/bend effect the soldering of the module and other component to the PCB over time and over may thermal cycles.

Thanks

Tahar

0 Ruixin Feng over 2 years ago in reply to Tahar Allag

TI__Intellectual 2445 points

Hi Tahar,

Is there POL module resin material inside LMZ31710?

Rayna

0 Tahar Allag over 2 years ago in reply to Ruixin Feng

TI__Mastermind 32420 points

Hello

I am checking internally, I will be back to you next week

Thanks!

Tahar

0 Tahar Allag over 2 years ago in reply to Tahar Allag

TI__Mastermind 32420 points

Hello Ruixin Feng,

Just got a confirmation, yes there is POL resin material in the device. There is about in 0.00336 mg is Ceramic substrate of the internal components of the and about 16mg on the Module and mold compound.

Thanks '

Tahar

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LMZ31710: PCB layout and stress question