[USMA:31055] Fw: Seeking info on JEDEC rules

[Euric]

Anyone want to help out Bob with some updated info?   Here is your chance!   Euric     ----- Original Message ----- From: Bob Neves To: Euric Cc: U.S. Metric Association Sent: Wednesday, 2004-09-08 16:53 Subject: RE: Seeking info on JEDEC rules Euric,   Thanks for the e-mail�  All that info has re-sparked my interest.  I will attempt to write a follow-up column for Circuitree Magazine based upon the information you have passed onto me.    I would like to see any information that the US Metric Association has that I can reference�. It is a worthy cause to keep pushing!!!     Best Regards, Bob Neves President Microtek Laboratories +1 (714) 999-1616 www.TheTestLab.com www.HATS-Tester.com     From: Euric [mailto:[EMAIL PROTECTED] Sent: Saturday, September 04, 2004 12:43 PM To: Bob Neves Cc: U.S. Metric Association Subject: Re: Seeking info on JEDEC rules   2004-09-04   Thanks for your reply.    I don't think the JEDEC specification is a command to use metric per se, but for the spacing of the pins on the IC chips to be in the format I mentioned.   I remember seeing it back in either the late '80s or early '90s.  It is the reason we have rounded metric spacing today (i.e. 0.65 mm, 0.50 mm and 0.40 mm), yes?  I tried searching on the web for it, but to no avail.  Do you think there is a way to find out?   I wouldn't say the US is metric-less.  About 40 % of US industry is either fully metric or partially metric.  Even those who try to avoid it can't.  Go to any factory and look around at the machines.  Even if a company produces nothing in metric, they may still have machines made with metric parts, especially fasteners.  Meaning that companies maintenance people must purchase and use metric parts and tools.   Your American cars use only metric parts and have so since the '70s.  Keeping it a "secret" from everyone except the mechanics has furthered the illusion American cars are not metric.  What a surprise to the back-yard mechanic who goes to service his car the first time and discovers the real truth.  Machine tools and other heavy equipment is made metric too.  John Deere, Caterpillar, Cummins, and Detroit Diesel etc. are major American companies that make metric machines (i.e. design, manufacture and use metric fasteners) now.    An acquaintance has informed me that the new Harley Davidson motor cycle called the V Rod introduced in the summer of 2001 is a metric machine from the ground up.  On 2003-07-01 Briggs and Stratton changed the fasteners on one of their engines from inch to metric, and the people at Briggs and Stratton have told him they plan to convert more of their engines to metric fasteners.    These changes may seem subtle to insignificant to some, but they are billion dollar companies that procure a lot of parts, creating a demand for metric materials driving up the cost of inch parts.  The real draw back to all of this is that the servicing industry has to pay a fortune to have double inventories of parts and tools.  I think if we added up this cost we would find it exceeds the supposed cost of conversion a multitude of times.  Not to mention the cost to the economy and life from dual unit usage that is ignored.   I'm sure the slowness you speak of comes also at a cost.  Sometimes there is a need to bite the bullet and make the change quickly to end the perpetual agony of being halfway between both ends.   I wonder if the Chinese are experiencing this problem.   I hope you are enjoying your stay in China and your work is a success.   Best Regards,   Euric             ----- Original Message ----- From: Bob Neves To: Euric Sent: Tuesday, 2004-08-31 09:45 Subject: RE: Seeking info on JEDEC rules   Euric,   I am sorry, but I do not recall any specific rule or requirement in a JEDEC specification for Metric�  I am glad and sorry to see that the US is become almost the ONLY metric less country (and that Burma and Liberia have moved forward)� I, as an engineer am a Metric Believer, bet still find it personally hard to use as the US system makes it difficult, but the electronics industry in general here in the states is still metric illigetimate (or is it illiterate)�.  They are being forced by design to change but it is SLOW!!!!   Great to see my old articles are still read occasionally!!! Thanks!!  And yes, the world�s best Chef�s are from Metric Countries (with the exception of the UK where I have yet to find good food)� I am writing this from China where our newest test facility is located�   Take Care,     Best Regards, Bob Neves President Microtek Laboratories +1 (714) 999-1616 www.TheTestLab.com www.HATS-Tester.com     From: Euric [mailto:[EMAIL PROTECTED] Sent: Sunday, August 29, 2004 7:06 AM To: Bob Neves Subject: Seeking info on JEDEC rules   2004-08-29   Mr. Neves,   While searching the Internet for information on a particular JEDEC rule on IC chip spacing, I came across the article you wrote in 1998 called "The Metric Mile".  See:   http://www.thetestlab.com/data/jan99.pdf   I would like your help in pointing me in the right direction.  I am looking for the specific JEDEC rule which requires that IC chip pin spacing be in metric dimensions.  If I am not mistaken, it is in the format X.XY, where X is any number from 0 to 9 and Y is restricted to being a 0 or a 5 and the units are millimetres.  I believe this ruling went into effect sometime around 1990.  Can you provide me with the name or JEDEC specification name/number for this rule?  I would appreciate it.   Can you also provide me info, if possible and not a lot of trouble, what has changed since you wrote your article in 1998.  I'd be curious to know.       In reference to your article, there is a mistake concerning the nations of Burma and Liberia.  Actually their economy (what little there is of it) is entirely metric.  They are considered non-metric only because their governments never made an official declaration to convert.  Due to heavy dependence of products and services from neighbouring countries, their purchases and use of products is metric.  Visitors to these countries have reported extensive metric usage.  The only things not metric are some machines left over from the colonial periods.  These two countries need to be taken off the list of non-metric countries.   As for cooking, I think Julia Childs did some  cooking with metric recipes to show how it would be done and everything worked out fine.  Don't forget, the world cooks in metric and the best chefs come from metric cooking countries.  That should tell you something there.   Thank you for your time and efforts,   Euric