I designed those in the late 70's in PCB's while at Experimental Physics Corp. They have been used with various degrees of success (depends on your expectations!) The major problem is the lack of predictability of the switch voltage. Many factors such as exact radius of the tip, solder mask and type or avoidance of, etc. But, they do work if you do not expect a narrow range of switch V threshold. For basic OV protection with additional better OV networks downstream, they work fine.
--- Gabi Hoffknecht <[email protected]> wrote: > > Hi all, > > I have seen PCB designs with two triangular shaped copper pads pointed > towards each other at very close proximity, meant as an air gap discharge > path for transients. Does anyone have information about such designs, > whether they work and how well ? At a breakdown voltage for air of 1 > Megavolt per meter, they should theoretically work: 10mil distance would > have a breakdown voltage of only 254V. Such a PCB design basically comes for > free, so I was thinking of adding it on top of my already existing series > impedance - TVS network. > Thanks in advance for your comments. > > Best regards, > Gabi Hoffknecht > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: [email protected] > Dave Heald: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > Jim Bacher: [email protected] > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" ===== Best Regards Hans Mellberg Regulatory Compliance & EMC Design Services Consultant By the Pacific Coast next to Silicon Valley, Santa Cruz, CA, USA 408-507-9694 __________________________________________________ Do You Yahoo!? Yahoo! Sports - Coverage of the 2002 Olympic Games http://sports.yahoo.com ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
