Well for example, I have just finished specifying what compliance re-testing I am going to need to do on 4 different products whose power conversion stages use IRF630's, IRF740's, IRF840's, and RFP50N06's, but the list goes on and on. If you are using power FET's in power electronics, chances are they have changed or will soon. The main manufacturers that come to mind are IR, Fairchild/Harris, Philips, and STM-Thomson. Not all have forced changes to the shrunk-die version - some have agreed to keep the old style available - and all have at least added a suffix to their markings on the devices so you can tell if it's the new revision die or old. In one case, however, we received modified parts with no markings differentiating them from the old rev parts, for almost a year with no communication from the mfr telling us about the change. We found out through other channels and then contacted them. They seem to be behaving as if fundamental changes to the performance and specifications of the part are none of our business.
I am re-doing radiated and conducted emissions, some thermal testing, and a bunch of functional testing and looking at waveforms on 4 different products affected by this change. Those are only the products I am responsible for - as a company we're doing functional testing and possibly compliance re-testing on many more products. This is not a simple component substitution exercise, if your products are or use power electronics! I would advise everyone potentially affected to have your procurement department look into this. Regards, Jim Eichner, P.Eng. Manager, Engineering Services Xantrex Technology Inc. Mobile Power web: www.xantrex.com <http://www.xantrex.com> Any opinions expressed are those of my invisible friend, who really exists. Honest. -----Original Message----- From: Michael Mertinooke [mailto:[email protected]] Sent: Wednesday, October 24, 2001 6:45 AM To: 'Jim Eichner' Subject: RE: Shrunk-die power MOSFET's and compliance Jim; I suspect that a lot of us just don't have time to investigate the latest subtleties involved in producing a new chip design sold under an old component part number. We order by manufacturer part number and when the order comes in we count the pieces and throw it in the stockroom. If there are reliability problems, most companies take a month or so for the news to get back from Field Service. Then the issue goes to Manufacturing because we know the design worked perfectly for X years, so Manufacturing must have built 'em wrong, or the PC house had a bad batch of boards or somebody screwed up the wave solder machine again or the stockroom was sweeping parts off the floor and dumping them back in the bins ... or a hundred other cockups that happen every day. By the time somebody finally figures out that the FETs are not performing as they should, it could be a year after the parts first hit the receiving dock. Instead of a general reference, perhaps you can provide a few part numbers? If I see such a list and my FETs are on it, then I sure as hell am going to look into it immediately! Thanks. Mike Mertinooke ------------------------------------------- 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: Michael Garretson: [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: No longer online until our new server is brought online and the old messages are imported into the new server.
