Yeah, I know. Several weeks ago, the design engineers suggested that I do something physically impossible, when I requested two caps in series...
And you would not believe some of the things that we have done to get the 'last few microamps" out of some of our last custom medical unit. Nothing to be 'humbled' about, we just kept banging away at the noisy stuff until the requirement for y-caps was mitigated. luck, Brian > -----Original Message----- > From: Marko Radojicic [mailto:[email protected]] > Sent: Monday, January 14, 2008 1:45 PM > To: [email protected]; Brian O'Connell > Cc: [email protected] > Subject: RE: Y1 cap info > > > Important EMI consideration: > > Two Y-caps in series = lower capacitance, twice the parasitics, less > filtering, and thus more conducted EMI. > > There is no free lunch: "Bomb-proof" Y cap design = reduced EMI > performance, unfortunately. > > > I agree with the statements that Y caps are exceedingly reliable and > that the need to put them is series is slim. > > The only applications that I am aware of that *don't* use Y-caps are > those that have extremely high requirements for leakage > current such as > some classes of medical devices. (I am humbled by the ability of our > medical device compliance colleagues to meet all the regulatory > requirements without these Y-caps.) > > > ...Marko - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
