That's my experience as well Doug. Thanks for taking the time to run the test.
Best Regards Charles Grasso Compliance Engineer Echostar Communications Corp. Tel: 303-706-5467 Fax: 303-799-6222 Cell: 303-204-2974 Pager/Short Message: [email protected] Email: [email protected] From: Doug Smith [mailto:[email protected]] Sent: Thursday, September 07, 2006 3:29 PM To: [email protected] Cc: Grasso, Charles; [email protected]; SI-List; emc-pstc Subject: Re: [SI-LIST] Re: Testing chips with system level specs Hi David and the group, I thought I would make some measurements. Humidity was not controlled but constant and likely about 40% and room temperature. I did many discharges into a ground plane through an Fischer F-65 (my favorite ESD current probe) over a period of a several minutes around 8 kV. Most all of the discharges were relatively slow but once in a while a fast event occurred. The occasional fast discharge happened whether the approach was fast or slow. Not sure if doing discharges in succession (5 seconds in between) affects later discharges. If so that might explain some of the results. It seems that there may be some remnants left over from the previous spark. Doug Pommerenke, David wrote: > Charles, > > On the "really fast discharges" using the Andy Hish simulatior I do not = > have the data here, as I am in Germany right now.=20 > > But if you look at > > http://web.umr.edu/%7Etiumr/davidjp/Jour_Estat__high_qual_1995.pdf > > (the link has %7 in it, that is OK) > > at figure 10 and figure 11. You see measurements of discharges at 10kV = > having risetimes of about 100ps or so. That is very close to the limit = > of the measuremetn system (SCD5000). > > The physics of the very fast discharges in air discharge is explained in > > > http://web.umr.edu/%7Etiumr/davidjp/ESDForum_1993.pdf > > (kind of old paper, but the physics have not changed). > > Regards, > > David Pommerenke > > -- ___ _ Doug Smith \ / ) P.O. Box 1457 ========= Los Gatos, CA 95031-1457 _ / \ / \ _ TEL/FAX: 408-356-4186/358-3799 / /\ \ ] / /\ \ Mobile: 408-858-4528 | q-----( ) | o | Email: [email protected] \ _ / ] \ _ / Website: http://www.dsmith.org - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
