Solder mask opening for LGA 12 LIS2DE12 ?

[antonius]

Dear Members,

I want to create a solder mask for LIS2DE12,

Is my solder mask correct ?

Have a look on my screen shot, thanks

[Eleon BORLINI]

Hi @antonius​ ,

it looks ok, check please your layout is compliant with the C and D rules (0.1m guard-band) of the TN0018 technical guidelines for the soldering that you reported.

The only issue you might face could be:

1. If the solder paste quantity is small, the risk is that it could be not well dispensed under the inter-connected pads (not a huge risk, indeed);
2. If the solder paste quantity is huge, you have to check that it doesn't flow out of the openings.

-Eleon

[antonius]

I can not see solder mask between pad, is that ok ? will it make a solder bridge? thanks

[antonius]

Do I need to add extra 0.1m ?

is solder mask at top solder (solder mask expansion ==>Specify expansion value? Add extra 0.1mm ?

[Eleon BORLINI]

>> Do I need to add extra 0.1mm?

I think you should not, since the spacing between the pads (the black area in your previous picture) looks ok.

Of course, additional 0.1mm would prevent issues in case of an over-dispensing of of solder paste.

-Eleon