Aw, just par for the course. For the record, Creepage _DISTANCE_ is defined as the shortest distance along the surface of insulation between (two) conductors. Apparently someone at TI omitted the word "distance" from their tutorial.
The word "Clearance" has no such need for the modifier "Distance" to take it from non-sequitor to sensible. The term "creepage" is defined as "Electrical leakage on a solid dielectric surface". In other words, creepage is a process, unlike creepage distance, which is a measurement of length. And pedantic too. ;) In any case, I hope you got a useful starter. Regards, aj >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On Behalf Of >[EMAIL PROTECTED] >Sent: Thursday, December 14, 2006 4:05 PM >To: Protel EDA Discussion List >Cc: Protel EDA Discussion List; [EMAIL PROTECTED] >Subject: Re: [PEDA] 500V power supply > >Hello all, > >Thanks for the wealth of information you have provided these >last couple of days...thanks for the attachments also. My >query was at an elemental level, but I can see that >discussions can get " quite interesting" even after a basic >rfi. FYI the 2004/2005 Power Supply Seminar issued by Texas >Instruments has the following definitions for "clearance and creepage: >"Clearance is defined as the shortest distance through air >between two conductive parts." >"Creepage is defined as the shortest distance between two >conductive parts along the surface of any insulating material >common to both parts." >(pg 1-9) >Semantics is the word that comes to mind... > >Carlos > > > > > > > > > >"Brad Velander" <[EMAIL PROTECTED]> >Sent by: [EMAIL PROTECTED] >12/14/2006 10:54 AM >Please respond to >Protel EDA Discussion List <[email protected]> > > >To >"Protel EDA Discussion List" <[email protected]> >cc > >Subject >Re: [PEDA] 500V power supply > > > > > > >Andrew, > No insult or derogatory meaning was read into your >comments. I have read your posts for enough years to understand that >typically you don't write with any personal malice. Well, >ahhh, possibly, >just maybe towards certain CAD software developers? 8^o > > I just wanted to make sure that the concept >of creepage >was not obscured or dismissed completely based on your >comments. It tends >to go beyond the basic PCB design in most cases but can very >easily become >a compromising situation to the end circuit performance or safety once >said PCB is put into enclosures/environments. > > Further, I am not knowledgeable enough to >give specific >instruction or more detailed instruction. For myself I typically >appreciate somebody just bringing the issues to light where I >can further >investigate them myself and determine if the "car" I am >looking at is a >Mazda or Toyota and get it right. > >Sincerely, >Brad Velander >Senior PCB Designer >Northern Airborne Technology >#14 - 1925 Kirschner Road, >Kelowna, BC, V1Y 4N7. >tel (250) 763-2232 ext. 225 >fax (250) 762-3374 > > >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] >Sent: Thursday, December 14, 2006 9:20 AM >To: [email protected] >Subject: Re: [PEDA] 500V power supply > > >Fair enough. So creepage isn't an IPC term, but it could just >as well be. >Imo, in this instance it's fluff and does little more than to >obfuscate >the underlying principle. Got kids? Okay, then do this, teach >the 4yr old >that "NO! It isn't a tree, it's an Oak...Got it?" or "No, >Bobby, that's >not a car, it's a Mazda". To me, that sounds like mud, or worse, like >unthinking rote. > >(SNIP) > > >____________________________________________________________ >You are subscribed to the PEDA discussion forum > >To Post messages: >mailto:[email protected] > >Unsubscribe and Other Options: >http://techservinc.com/mailman/listinfo/peda_techservinc.com > >Browse or Search Old Archives (2001-2004): >http://www.mail-archive.com/[email protected] > >Browse or Search Current Archives (2004-Current): >http://www.mail-archive.com/[email protected] > > > >____________________________________________________________ >You are subscribed to the PEDA discussion forum > >To Post messages: >mailto:[email protected] > >Unsubscribe and Other Options: >http://techservinc.com/mailman/listinfo/peda_techservinc.com > >Browse or Search Old Archives (2001-2004): >http://www.mail-archive.com/[email protected] > >Browse or Search Current Archives (2004-Current): >http://www.mail-archive.com/[email protected] > > This e-mail transmission and its attachments may contain information from Avtron Manufacturing, Inc. that is proprietary, privileged and/or confidential and is intended exclusively for the person(s) to whom it is addressed. Any use, copying, retention or disclosure by any person other than the intended recipient or the intended recipient's designees is strictly prohibited. If you have received this message in error, please notify the sender immediately by return e-mail and delete all copies. ____________________________________________________________ You are subscribed to the PEDA discussion forum To Post messages: mailto:[email protected] Unsubscribe and Other Options: http://techservinc.com/mailman/listinfo/peda_techservinc.com Browse or Search Old Archives (2001-2004): http://www.mail-archive.com/[email protected] Browse or Search Current Archives (2004-Current): http://www.mail-archive.com/[email protected]
