Dear Group, In dry conditions, not only the charging processes are enhancec, but the severity (less risetime, higher peak current) is enhanced in general. For both reasons, it is not uncommen to see ESD problems move around the world with the local seasons.
Still, I would always try to debug the problem in contact mode. The effect on humidity on the electromagnetic properties is in general very small. Aim of the debugging should be to identify the traces, nets of PINs that are effected. Locally injecting pulses via direct, capacitive, inductive or differential injection has prooved to be an effective tool for achieving this. David -----Ursprüngliche Nachricht----- Von: Gibling, Vic [mailto:vic.gibl...@marconi.com] Gesendet: Mi 12.06.2002 02:26 An: emc-p...@majordomo.ieee.org Cc: Betreff: An ESD question Dear Group I tried to find David Pommerenke article's in the Journal of ESD on the Web but alas no downloadable version was found, so may I ask the group a question? We have an ESD field failure which is occurring in dry hot countries ( no surprise )which can be recreated with an ESD of -800V. In an attempt to get a high incidence of discharges we used a dehumidifier to create a dry environment. The result was a reduction in discharges. Thinking the problem through -now- as a dry atmosphere will encourage the production of high level ESD and a humid environment inhibits the charge to a lesser level, presumably because it 'leaks' away. Then is it wrong for us to attempt to 'dry' the local atmosphere in the hope of gaining consistent ESD from an ESD gun, that is to say the more humid the environment the more efficiently the discharge will transfer to the victim? Incidentally, to add to the thread regarding intermediate level testing for ESD and EFT. This exercise has revealed different failure mechanisms at different ESD levels. Your views would be appreciated. Vic Gibling Compliance Engineer Marconi Applied Technologies ------------------------------------------- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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" ------------------------------------------- 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: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@attbi.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org 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"
