The discharge will be much more energetic than a CDM event as there is MUCH more energy stored off the card than the card itself in this case, but passes through the card. The capacitance is much higher than Tom realizes below. Somewhere below a CDM event and an IEC event.
eration is how will the card stand up to hundreds or thousands of small, ubiquitous ESD events that cannot be felt by humans but cause slow degradation from not only insertion but handling over several months. No one tests for that yet. I have designed an apparatus that does that job and it has proven very useful. Doug Smith University of Oxford, Course Tutor Department for Continuing Education Oxford, Oxfordshire, United Kingdom -------------------------------------------------- Doug Smith P.O. Box 60941 Boulder City, NV 89006-0941 TEL/FAX: 702-570-6108/570-6013 Mobile: 408-858-4528 Email: d...@dsmith.org Web: http://www.dsmith.org -------------------------------------------------- On Wed, 22 Mar 2017 07:27:33 +0900, "T.Sato" wrote: On Mon, 20 Mar 2017 19:24:23 +0000, "Grasso, Charles" wrote: > Aside from the obvious air discharge tests around the SD card slot (with and > without the SD card installed) are there > any concerns regarding the ESD performance of the SD card during INSERTION? Only a guess... SD card may be charged before insertion, and may cause discharge from those contacts when inserted. This situation may slightly similar to that simulated with charged device model (CDM), and the discharge may be much faster than that of IEC 61000-4-2 and ISO 10605. However, it's capacitance is low, and I think it will not become a serious problem in general. In case of Compact Flush card, I ever heard of a case where metalized label on the card created an unexpected path for electrostatic discharges and caused a problem when hold by hand and inserted to a device. Regards, Tom -- Tomonori Sato URL: http://t-sato.in.coocan.jp - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas Mike Cantwell For policy questions, send mail to: Jim Bacher: David Heald: Doug Smith University of Oxford Course Tutor Department for Continuing Education Oxford, Oxfordshire, United Kingdom -------------------------------------------------- Doug Smith P.O. Box 60941 Boulder City, NV 89006-0941 TEL/FAX: 702-570-6108/570-6013 Mobile: 408-858-4528 Email: d...@dsmith.org Web: http://www.dsmith.org -------------------------------------------------- - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe) List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
