Gabriela Bogdan wrote:
>
> Hi, TechNetters!
> Could you please share with me your experience about pro and con's
> regarding solder mask
> between fine pitch-16mil- pads in relation to the finish of the PCB pads
> ?
> Not being greedy, I'll save the next question for after some answers.
> Thank you,
> Gaby
>
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 Gaby -

I strongly recommend solder mask (LPI) between the pads on all fine
pitch.  Seveal years ago, we designed a process development test board
which had both "pad windows" (no mask between pads on one side of a QFP
footprint) and mask between pads. The QFP's and pad windows were in
different orientations on the same board.  The results were that we had
significantly less bridging with mask between the pads. For the last few
years, we have assembled .016 mil parts with mask between the pads. You
may want to consider another PC Board fabricator.  Ed Valentine/

--

ProTronics, Inc.
861 Old Knight Road
Knightdale, NC 27545
Phone: (919) 217-0007, Fax: (919) 217-0050
http://www.protronics-inc.com

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