group, pertaining to esd and LCD's is subjected to the air and / or contact discharge? or is it taboo...and ESD is only discharged to the frame around the LCD itself. thnaks in advance Richard.
Richard A. Stone Excel Switching Corporation Compliance 75 Perseverance Way Hyannis, MA. 02601 508 862 3311 ph. 508 862 3020 fax This email message and any attachments to it contain confidential information that is intended only for the person or entity to which it is addressed. Any review, retransmission, dissemination, printing, or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. If you received this in error, please delete it or inform the sender. From: [email protected] [mailto:[email protected]]On Behalf Of [email protected] Sent: Friday, January 30, 2004 11:18 AM To: [email protected]; [email protected] Cc: [email protected] Subject: RE: Re: LCD ESD issues I suspect it is the LCD driver electronics and not the LCD that is being upset by the ESD discharge. Is there time for a redesign? If so, provide a path for the ESD current that bypasses the LCD electronics. And design so that the ESD electronics does not jump in voltage versus the incoming signals. You have a 10 amp pulse with a 1ns risetime to deal with. This can develop 50-100 volts across 1cm of wire. Sometimes capacitive bypassing across input lines can help- chosen so that the desired signals still work but the ESD pulse is ignored. No lead length is allowed with 100 volts per cm. Dave Cuthbert Micron Technology From: [email protected] [mailto:[email protected]]On Behalf Of [email protected] Sent: Thursday, January 29, 2004 5:54 PM To: John Woodgate Cc: emc-pstc @ majordomo . ieee . org Subject: Re: Re: LCD ESD issues In this case, the Australian National Gaming Standard stipulates that no noticable effects are acceptable up to 15kV air discharge. > John Woodgate <[email protected]> wrote: > > > I read in !emc-pstc that [email protected] wrote (in > <200401290411. > [email protected]>) about 'LCD ESD issues' on > Thu, 29 Jan 2004: > > >I am currently having problems with EN61000-4-2 ESD testing on LCD > >screens (I have tried 3 manufacturers all with the same result). The > > >problem is that discharging on the LCD or a near by metal grounded > >object causes the LCD to blank (black screen) for about 1/2 a > second. > >The particular standard does not allow for self recoverable effects, > so > >this is not considered acceptable. > > 61000-4-2 is a Basic Standard and has no business to be setting > requirements. It should only specify the test methods. Pass/fail > requirements are in Generic and Product(-family) Standards. > > Which date version of the EN are you looking at, with or without > which > amendments? What is the clause number where this 'requirement' is > set. > > Criterion B (self-recovery) is specifically intended to be applied to > transient disturbances. > -- > Regards, John Woodgate, OOO - Own Opinions Only. > The good news is that nothing is compulsory. > The bad news is that everything is prohibited. > http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ieee-pses.org/ > > 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://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ 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://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ 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://www.ieeecommunities.org/emc-pstc This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ieee-pses.org/ 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://www.ieeecommunities.org/emc-pstc
