6 years ago in a product that was failing our radiated emissions limits I tried a ferrite sheet that was placed under the cpu clock oscillator with holes for the leads to run through. The material was about 2mm thick. Unfortunately I am unable to find the manufacturers part number at this time. We never released that part to manufacturing. The clock fundamental frequency was 20MHz and there was an emission at 225MHz that was over the limit. The ferrite reduced that emission about 9dB.
Darrell -----Original Message----- From: Knighten, James L [mailto:jk100...@exchange.sandiegoca.ncr.com] Sent: Friday, April 02, 1999 11:00 AM To: EMC-PSTC Subject: RE: RE: Ferrite pads vendors To All: Regarding these layers of ferrites that can be placed either above, or below an IC, a few people have indicated that "they work." Can anyone be more specific? What does it mean that "they work?" Jim Dr. Jim Knighten e-mail: jlknigh...@ieee.org <mailto:jlknigh...@ieee.org> Senior Consulting Engineer NCR 17095 Via del Campo San Diego, CA 92127 http://www.ncr.com <http://www.ncr.com> Tel: 619-485-2537 Fax: 619-485-3788 --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).
