[SOLVED] via on capacitors plane

[miskol]

Hi,

1) in an attempt to save routing spaces, is it okay to put via on capacitor smt planes where the via and the capacitor plane is connected to the same route.

2) is it okay to put vias under the microcontroller? i think vias will not heighten the base which will make it difficult to solder the smt microcontroller. or am i wrong?

Thank you.

 

[keith1200rs]

1) Assuming you mean - can you put vias on SMT capacitor pads the answer is no.

2) Vias under devices are usually fine.

Keith.

 

[hobbss]

If space is your driving priority, you can put vias in the pads -- it just leads to more expensive manufacturing costs. To ensure high yield and reliability, you would need to have the manufacturer fill the vias (best), or tent them on the back side (not as good). If you are hand soldering the board, this is less critical -- but who really likes to hand solder 0402 or 0201 decoupling capacitors?

Screaming Circuits is a cheap assembly house. One of their engineers has a pretty good blog about via-in-pad. He was talking mainly about the heat slugs of QFN packages, but the same principles would apply to capacitor pads.

Screaming Circuits: Via in Pad

 

[miskol]

thanks hobbss, good info.