Hi Bogert
Happy turkey day!
I have to ask, do you apply conformal coating? If so, how do you apply
it under things like pin grid array parts? Quad flatpacks? Vertical
plug connectors where you don't have access to the top side solder
joints? DC/DC converter blocks? SMT Chip resistors?
Sorry, but I've got to disagree with you. I've never seen a drawing
that specified "no coating required" under shadowed parts, and I have
never talked with a quality engineer or process engineer who thought
that meant coating under the parts (maybe you are the first, what is
your job???).
regards,
Graham Collins
Process Engineer,
L-3 Communications Electronic Systems Inc.
Halifax
(902) 873-2000 ext 6215
>>> [log in to unmask] 11/23/06 03:27PM >>>
November 23, 2006
Dave, happy turkey day. My response did not mean I agree that
conformal coating should in fact be applied under a component. What I
indicated was that if the drawing specifically mandated that the
assembly be conformal coated, then the expectation is that coating must
be applied under, over, and everywhere else on the assembly unless the
assembly drawing specifically requires masking free of certain areas
from conformal coating.. If conformal coating should not be applied
under a part, then the drawing needs to say so.
----- Original Message -----
From: David D. Hillman<mailto:[log in to unmask]>
To: [log in to unmask]<mailto:[log in to unmask]>
Sent: Monday, November 20, 2006 6:27 PM
Subject: Re: [TN] BGA and conformal coating
Hi Bogert! Sorry but I respectfully disagree. If the contract
requires the
assembly to be conformal coating and provides no other process
guidance
then I would process the assembly in accordance with best industry
practice/accepted material process practice for the particular
conformal
coating material specified. As other TechNettees have documented,
intentionally forcing AR or UR conformal coating under a component is
not
standard conformal coating practice as the such an action results in
degraded component/product integrity due to CTE mismatch for many
use
environments. However, if I was using a paralyene conformal coating,
standard material process practice is quite the opposite - paralyene
conformal coating is design to coat all pwa surfaces. The
application
process for each conformal coating material dictates how/where it
should be
applied unless there are specific instruction that deviate from
standard
practice (such as a specific exclusion area for RF, etc.).
Dave
- Bogert
<[log in to unmask]<mailto:[log in to unmask]>>
Sent by: TechNet
To
<[log in to unmask]<mailto:[log in to unmask]>>
[log in to unmask]<mailto:[log in to unmask]>
cc
11/20/2006 03:52
Subject
PM Re: [TN] BGA and conformal
coating
Please respond to
TechNet E-Mail
Forum
<[log in to unmask]<mailto:[log in to unmask]>>
; Please respond
to
- Bogert
<[log in to unmask]<mailto:[log in to unmask]>>
If the contract assembly drawing requires the assembly to be
conformal
coated, unless it also allows the area under the BGA to be free of
coating,
then you are in violation of the contract drawing regardless of what
610
says or does not say.
----- Original Message -----
From: David D.
Hillman<mailto:[log in to unmask]<mailto:[log in to unmask]>>
To:
[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>
Sent: Monday, November 20, 2006 2:20 PM
Subject: Re: [TN] BGA and conformal coating
Hi Joe - Your statement......." type AR or type UR does not coat
the BGA
solder balls/solder connections located under the BGA so you are
violating
the acceptability requirements in IPC-A-610" has me some confused.
What
IPC-A-610 requirement is violated?
Dave Hillman
Rockwell Collins
[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>
"Macko, Joe @
IEC"
<joe.macko@L-3COM<mailto:joe.macko@L-3COM<mailto:joe.macko@L-3COM<mailto:joe.macko@L-3COM>>
To
.COM>
[log in to unmask]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[log in to unmask]>>
Sent by: TechNet
cc
<[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>>
Subject
Re: [TN] BGA and conformal
coating
11/20/2006 12:47
PM
Please respond to
TechNet E-Mail
Forum
<[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>>
; Please respond
to
"Macko, Joe @
IEC"
<joe.macko@L-3COM<mailto:joe.macko@L-3COM<mailto:joe.macko@L-3COM<mailto:joe.macko@L-3COM>>
.COM>
Vered,
I would start with IPC-A-610 and J-STD-001 documents. One item that
is
over
looked is that spraying a board with for example type AR or type UR
does
not
coat the BGA solder balls/solder connections located under the BGA
so you
are violating the acceptability requirements in IPC-A-610!
Good luck,
- Joe
-----Original Message-----
From: Vered BS [mailto:[log in to unmask]]
Sent: Monday, November 20, 2006 8:40 AM
To:
[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>
Subject: [TN] BGA and conformal coating
looking for reviews/articles or case studies regarding conformal
coating
on
BGA
for military/aerospace environment
Appreciate any comment or sharing your experiance
Thanks
Vered
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to
[log in to unmask]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>:
SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives<http://listserv.ipc.org/archives<http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>>
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16><
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16>>
for additional information, or contact Keach Sasamori at
[log in to unmask]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>:
SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives<http://listserv.ipc.org/archives<http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>>
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16><
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16>>
for additional information, or contact Keach Sasamori at
[log in to unmask]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[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]<mailto:[log in to unmask]<mailto:[log in to unmask]<mailto:[log in to unmask]>>:
SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives<http://listserv.ipc.org/archives<http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>>
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16><
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16>>
for additional
information, or contact Keach Sasamori at
[log in to unmask]<mailto:[log in to unmask]><
mailto:[log in to unmask]<mailto:[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]<mailto:[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]<mailto:[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]<mailto:[log in to unmask]>: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16>
for additional information, or contact Keach Sasamori at
[log in to unmask]<mailto:[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]<mailto:[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]<mailto:[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]<mailto:[log in to unmask]>: SET Technet Digest
Search the archives of previous posts at:
http://listserv.ipc.org/archives<http://listserv.ipc.org/archives>
Please visit IPC web site
http://www.ipc.org/contentpage.asp?Pageid=4.3.16<http://www.ipc.org/contentpage.asp?Pageid=4.3.16>
for additional information, or contact Keach Sasamori at
[log in to unmask]<mailto:[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
-----------------------------------------------------
---------------------------------------------------
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
-----------------------------------------------------
|
