Good question Amund. Adding a "diversion plane" is fairly standard procedure when it comes to high-end handheld calculators, and the like. It also is a good ESD solution for troubleshooting or retrofit of a product. Theoretically, I believe that replacing the separate diversion plane with an additional layer within the PC board should work the same - if implemented properly. That's really the key. A solid metal plane is really two separate isolated planes, if skin effect due to high-frequency signals is considered. Therefore, (in theory) if the ESD current is diverted to the "lower" plane, it should not affect the circuitry on the PC board. If, in implementing this extra plane, ESD currents are allowed to "leak" to the "upper" plane, then all bets are off. I believe things like vias or any type of clearance holes could easily compromise this added plane.
Cheers, Ken _______________________ Kenneth Wyatt Wyatt Technical Services LLC Woodland Park, CO Email Me! | Web Site | Blog The EMC Blog (T&M World) Subscribe to Newsletter Connect with me on LinkedIn On Mar 28, 2013, at 4:32 AM, Amund Westin wrote: > Hi Ken, > > Interesting reading. > > Protecting low-cost products from ESD > ð What about having an extra PCB layer with solid ground plane? Will it be > equal to a separate metal plane? Maybe this metal plane will be a fix during > test at lab to verify ESD compliance. > > Cheers! > > #Amund > > Fra: Ken Wyatt [mailto:[email protected]] > Sendt: 27. mars 2013 16:34 > Til: [email protected] > Emne: [PSES] March EMC blog postings > > Hi All, here's a recap of my blog postings this month. > > Review: Amazing USB 5.35 GHz spectrum analyzer > (http://www.tmworld.com/electronics-blogs/the-emc-blog/4410523/Review--Amazing-USB-5-35-GHz-spectrum-analyzer) > > Always on the lookout for useful, but inexpensive test equipment, I recently > ran across the Triarchy Technologies USB spectrum analyzer, model TSA5G35. > The one thing that really struck me was the whole thing was built into a USB > dongle, just a little larger than a memory stick. What's more, the advertised > frequency range was 1 MHz to 5.35 GHz. This, I had to see for myself. > > EMC troubleshooting parts storage > (http://www.tmworld.com/electronics-blogs/the-emc-blog/4408438/EMC-troubleshooting-parts-storage) > > For those of you who regularly troubleshoot EMC issues, wouldn't it be > convenient to have all your "fix-it" parts all in one place? > > Milwaukee EMC symposium > (http://design-4-emc.com/2013/03/23/milwaukee-emc-mini-symposium-march-2013/) > > I was honored to be the featured speaker at the 13th annual EMC Society > Chapter of the IEEE Milwaukee Section “EMC Mini-Symposium” this last March > 19th. Hosted and managed by EMC engineer Jim Blaha (GE Medical), this was > actually no mini-symposium – but is the largest regional gathering of EMC > engineers in the country. There were a record 180 engineers from around the > area, as well as a record 42 vendors showing their wares (with pictures). > > Protecting low-cost products from ESD > (http://www.theconnectingedge.com/author.asp?section_id=2600&doc_id=259511) > > The best protection from ESD is a fully-shielded enclosure with all I/O and > power connectors well-bonded to the enclosure. Many low-cost products, > however, lack shielded enclosures because of cost. That creates a problem in > protecting the circuitry from ESD. > > Bond those connectors, save your day > (http://www.theconnectingedge.com/author.asp?section_id=2600&doc_id=260359&;) > > The No. 1 radiated emission issue -- and the one that frankly keeps me in > business -- is poor cable shield terminations (bonding) to product > enclosures. It's such a simple problem to solve, but lack of knowledge by > designers is largely to blame. > > Hope your week is going well! > > Ken > _______________________ > Kenneth Wyatt > Wyatt Technical Services LLC > Woodland Park, CO > Email Me! | Web Site | Blog > The EMC Blog (T&M World) > Subscribe to Newsletter > Connect with me on LinkedIn > > - > ---------------------------------------------------------------- > 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 > <[email protected]> > > 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://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]> > - ---------------------------------------------------------------- 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 <[email protected]> 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://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]>
