I've always let the board density and thickness be the determining factors as to what type I should use,
but I always check with the client before going to a type of via that could add cost to the board.
Sometimes there's no choice but to go for via-in-pad, or blind & buried, micro-via etc , but I always try to keep it simple.
I also find that knowing up front what type of via will be used will also affect the placement , since less room is needed if
Via-inpad is used instead of the traditional dog bone.
And I also put the via tolerances at +.003"/- whatever the via hole size is ...it gives the manufacturer lots of leeway.
Regards,
Andre Demers
CMRSummit Technologies
-----Original Message-----
From: DesignerCouncil [mailto:[log in to unmask]] On Behalf Of Pete
Sent: September-12-14 9:03 AM
To: [log in to unmask]
Subject: Re: [DC] Vias
OK, this might lead to a productive result of this discussion:
Steve days: "We fill via's with conductive epoxy, and plate over everything with ENIG."
Is this a rule? Every board? Why? You may be incurring needless cost. If you do require fill on all boards because of your products, are you taking advantage of that fill in places where it's not needed, but exists anyway? There's always another way to look at everyday things.
There are a lot of things we all do, because we always have. I am enjoying this discussion because I like to re-think some of the things I get used to thinking are just simple concepts. For example, I never really thought about Veronika's point that vias that are plated closed are closed, but not filled. I've always included a note allowing small vias (<.35mm) to be plated closed. Only to make it easier for the fabricator, increasing yield and lowering costs. I'm not looking for any design benefit, and as Veronika pointed out, there really isn't any. (That I currently recognize)
Pete
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 16.0.
To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL) For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
---------------------------------------------------------------------------------
______________________________________________________________________
This email has been scanned by the Symantec Email Security.cloud service.
For more information please contact helpdesk at x2960 or [log in to unmask]
______________________________________________________________________
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 16.0.
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF DesignerCouncil.
To temporarily stop/(restart) delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL/(MAIL)
For additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
---------------------------------------------------------------------------------
|
