I read in !emc-pstc that Paolo Peruzzi <[email protected]> wrote (in <[email protected]>) about 'PCB floating area layout', on Mon, 25 Feb 2002:
>1) Is it best to minimize the HF capacitive coupling between the earthed >ground and the floating ground or to maximize it? >2) Is it best to reduce the amount of the floating ground or to increase >it? I don't think there is any definitive answer to either question. It depends on how the coupling causing the emission is occurring. But you can experiment, can you not? Add some small ceramic capacitors between the grounds - several small ones in different places may be better than one big one. Consider the frequency range of the emissions to decide the values - 100 nF is no good at 100 MHz! -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! ------------------------------------------- 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"
