1). Have the IPC-7351 specs replaced the IPC-SM-782 specs?
The 782 is obsolete. The new standard is flying off the shelves @IPC from
what I hear; many companies started adopting the new standard because the
old standard was created a long time ago when cell phones were the size of
bricks. Sounds trite, but technology changes.
2). Which spec should we be designing to?
The industry dictates that, really. A growing number of companies are
starting to use the new 7351, especially since it allows greater flexibility
than the 782 (has three tiers), and comes available with a growing amount of
free library documentation for thousands of parts. Does this mean you can't
design to the 782? No, I'm sure there are still people who still use
obsolete 'standards' like the D-275 (was replaced in 1998 by the far more
comprehensive IPC-2220 Series).
3). Why have the specs changed?
See answer #1 above.
4). Are the IPC-7351 Specs incorrect?
The industry decides what is correct and what isn't. As Matthew said, if you
still use the 782, your work is not necessarily wrong, but in choosing so,
you are however limiting the amount of resources you can use to make your
design sooo much more efficient. The earlier companies adopt the new
standard, the more they benefit from first mover advantage because its not a
question of whether or not the 7351 will completely replace the 782 in the
industry. It's a questions of when (ie it will happen). Some lead, others
follow, some try to do both. Neither is wrong, it depends on your business
model.
Nick
-----Original Message-----
From: DesignerCouncil [mailto:[log in to unmask]] On Behalf Of Matthew
Lamkin
Sent: Friday, July 29, 2005 8:32 AM
To: [log in to unmask]
Subject: Re: [DC] IPC-SM-782 VS IPC-7351
And does this necessarily make any board that has been designed to the
IPC-SM-782A specs wrong/old technology/bad etc?
Most likely not, but I'm sure that Nick will be able to answer your
question.
Matthew Lamkin.
-----Original Message-----
From: DesignerCouncil [mailto:[log in to unmask]]On Behalf Of Rich
Schutz
Sent: Friday, July 29, 2005 2:28 PM
To: [log in to unmask]
Subject: [DC] IPC-SM-782 VS IPC-7351
We have been using IPC-SM-782 specs for years and have no problems. We
request that are customers use the IPC-SM-782 specs when designing there
PCBS. Some questions have come up in regards to the IPC-7351 specs, which
some of our customers are using for there designs. We typically review the
chip components on all of the boards we manufacture, in doing so I came
across an issue where the chip components specs have changed between the
IPC-782 and IPC-7351. My questions are:
1). Have the IPC-7351 specs replaced the IPC-SM-782 specs?
2). Which spec should we be designing to?
3). Why have the specs changed?
4). Are the IPC-7351 Specs incorrect?
Rich Schutz
CAD Engineer
Phone: 440-358-5217
Fax: 440-358-5201
Apsco, Inc
3700 Lane Road
Perry, Ohio 44081
----------------------------------------------------------------------------
-----
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV
1.8d
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)
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail 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
----------------------------------------------------------------------------
-----
----------------------------------------------------------------------------
-----
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV
1.8d
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)
Search previous postings at: www.ipc.org > On-Line Resources & Databases >
E-mail 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
----------------------------------------------------------------------------
-----
---------------------------------------------------------------------------------
DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d
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)
Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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
---------------------------------------------------------------------------------
|
