Jerry - Thanks for providing your open comments. My comments here are not particular to any simulation tool. What caught my attention was your mention of a comparative analysis of the software application to "human design rules".
The majority of the boards we typically evaluate are component-dense, multilayer, typically 10" X 12" in size, deployed in shielded enclosures for large systems, with various I/O. Based on my own personal experiences and conversation with other EMC engineers, for my customer base my preference is just the opposite (opt for rules-based approach over simulations). I am not aware of any package that can truly assess a board in a system (after all, that's where the compliance is ultimately stated), considering all the different mechanisms possible, and found that I ended up spending a great deal of time chasing down IBIS and other models (the accuracy of which is also questionable), just to run the simulation. The typical component data sheet lists maximum and typical rise times, but not minimum. To counter this, some engineers have taken the approach of worst-case model assumption, which sometimes leads to questionable simulation results. My opinion is that the process of heaping worst-case assumptions upon one another often leads to a destination of EMC overdesign. Some time ago I saw an interesting commentary by Dr. Howard Johnson on EMC simulation, and tend to agree that it is extremely difficult for any one tool to be both all encompassing and valid. I believe EMC simulation tools are excellent for gaining insight into the various mechanisms, and coupled with a variety of practical experiences, leads to an efficient deployment of design rules on an individual design basis. But I always keep my eyes open to all the latest developments, and ears available to all knowledgeable opinions! Regards, Mark Gill, P.E. EMC/Safety/NEBS Design Nortel Networks - RTP, NC, USA > -----Original Message----- > From: Meyerhoff Jerry-G10812 [SMTP:[email protected]] > Sent: Thursday, May 25, 2000 6:12 PM > To: 'Dale Albright'; [email protected] > Subject: RE: Quiet Expert > > > Dale & Group : > > We're just now evaluating Quiet Expert for single PCB automotive embedded > (microprocessor )controller designs. Got training & will run some typical > designs through it to see if it catches EMC design weaknesses > easier/faster/more surely than > by human design rule checking , thus eliminating wasted design revisions / > turns / spins. > > What is your application & what benefits are you looking for ? > > Anyone else out there using it? > > Is there a user's group ? > > Best regards, > Jerry Meyerhoff > Principal Staff Engineer > Motorola AIEG [Automotive & Industrial Electronics Group] of > IESS [ Integrated Electronic Systems Sector ] > 4000 Commercial Ave > Northbrook Il. 60062 > 847/480-5686 voice > 847/205-2452 fax > [email protected] > 5/25/2000 > > -----Original Message----- > From: Dale Albright [mailto:[email protected]] > Sent: Wednesday, May 24, 2000 4:38 PM > To: [email protected] > Subject: Quiet Expert > > Group, > > I am in the process of evaluating an EMI analysis tool. The program is > "Quiet Expert" by Innoveda (formally Viewlogic as I understand it). Is > anyone using this program or have you evaluated it along with others? > > Dale > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > To cancel your subscription, send mail to: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Jim Bacher: [email protected] > Michael Garretson: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > To cancel your subscription, send mail to: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Jim Bacher: [email protected] > Michael Garretson: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > >
