TECHNET Archives

February 2007

TechNet@IPC.ORG

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Lee parker <[log in to unmask]>
Reply To:
TechNet E-Mail Forum <[log in to unmask]>, Lee parker <[log in to unmask]>
Date:
Mon, 12 Feb 2007 12:41:37 -0500
Content-Type:
text/plain
Parts/Attachments:
text/plain (108 lines)
Dave

Most of the domestic shops I work with, now have pad to SM registration of 2 
mils, this allows a 4 mils (or more) dam on typical 20 mil pitch features 
which is generally adequate. I imagine that the shops in Europe have the 
same capability as here in the colonies. Of course the only shops of 
interest here are the ones that are used by Steve. It might also be 
beneficial to slightly reduce the feature size.

Best regards

Lee

I. Lee Parker, Ph.DO.
JPL Consultants LLC
804 779 3389


----- Original Message ----- 
From: "David Greig" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, February 12, 2007 12:33 PM
Subject: Re: [TN] LPI soldermask resolution


> Hi Steve
>
> Typical pad to mask clearances are 3mil, so that would leave only a 2mil 
> strip of mask. 5mil is more commonly required by most
> fabs. With round pads (BGA) the fab may accept it, but most would not 
> countenance a 2mil strip if it's any length.
>
> While it may be useful as a surface tension modifier, it's almost never 
> present in the case of fine pitch parts where the
> challenge of bridging is greater.
>
>
> Best Regards
>
> David Greig
> ______________________________
> GigaDyne Ltd
> 5 Albany Business Centre
> Gardeners Street
> Dunfermline KY12 0RN
> United Kingdom
> t: +44 (0)1383 624 975
> www.gigadyne.co.uk
> ______________________________
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory
> Sent: 12 February 2007 17:11
> To: [log in to unmask]
> Subject: [TN] LPI soldermask resolution
>
> Mornin' All!
>
> What kind of resolution should a LPI be able to give you? Specifically, 
> LPI's should be able to give you a solder mask dam
> between 20-mil pitch leads if you have 8-mils of space between the pads 
> shouldn't it?
>
> Thanks!
>
> -Steve Gregory-
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 1.8e To 
> unsubscribe, send a message to [log in to unmask] with
> following text in the BODY (NOT the subject field): SIGNOFF Technet To 
> temporarily halt or (re-start) delivery of Technet send
> e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE 
> mailing per day of all the posts: send e-mail to
> [log in to unmask]: SET Technet Digest Search the archives of previous posts 
> at: http://listserv.ipc.org/archives Please visit IPC
> web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional 
> information, or contact Keach Sasamori at
> [log in to unmask] or 847-615-7100 ext.2815
> -----------------------------------------------------
> --
> Virus scanned by Lumison.
>
> ---------------------------------------------------
> Technet Mail List provided as a service by IPC using LISTSERV 1.8e
> To unsubscribe, send a message to [log in to unmask] with following text in
> the BODY (NOT the subject field): SIGNOFF Technet
> To temporarily halt or (re-start) delivery of Technet send e-mail to 
> [log in to unmask]: SET Technet NOMAIL or (MAIL)
> To receive ONE mailing per day of all the posts: send e-mail to 
> [log in to unmask]: SET Technet Digest
> Search the archives of previous posts at: http://listserv.ipc.org/archives
> Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 
> for additional information, or contact Keach Sasamori at [log in to unmask] or 
> 847-615-7100 ext.2815
> -----------------------------------------------------
> 

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------

ATOM RSS1 RSS2