[sdiy] electrosensitive devices

[Tim Ressel]

Yo,

(my fav topic)...

In fact, you can hold a neon light near where the tape
comes off the roll, and the light will flash from the
charge on the tape. A Vandegraff generator is nothing
more than a spinning rubber belt with a wire rubbing
on it.

--Tim

--- Scott Gravenhorst <music.maker at gte.net> wrote:
> You can actually *see* sparks from many tapes as you
> pull it off the roll in a
> very dark room when the air is dry.
> 
> When I worked for DEC, we saw a training movie where
> some engineers took an MOS
> transistor and tossed it back and forth just a few
> feet, each engineer inserting
> it into a transistor tester until the device failed.
>  Both engineers were wearing
> wrist straps.  This was to illustrate that all it
> takes to produce sufficient
> charge is friction with air molecules as it flew. 
> It took only a few tosses for
> the device to fail.
> 
> 
> patchell <patchell at silcom.com> wrote:
> >    When I worked at Hughes Aircraft, the 3M people
> gave a demonstration (a
> >sales pitch for their anti static equipment and
> materials), where they measured
> >the gate leakage of a FET, then put it into a
> "pink" anti static bag, and 1 foot
> >away from the back, pulled about 1 foot of scotch
> tape off a tape dispenser.
> >They then put the fet back into the leakage tester
> to show that the gate had be
> >severly damaged.  So the answer is that you do not
> need to see a spark in order
> >for the there to be static damage.
> >
> >Stephen Begin wrote:
> >
> >> One more question about static then...is it
> possible for a significant
> >> amount of static to transfer from say...my finger
> to an expensive cmos chip,
> >> without that audible "zap" sound?
> >> -steve
> >>
> >> ----- Original Message -----
> >> From: "Peter Grenader"
> <petergrenader at mksound.com>
> >> To: "Stephen Begin" <trypannon at hotmail.com>;
> "synth"
> >> <synth-diy at dropmix.xs4all.nl>
> >> Sent: Friday, April 04, 2003 10:43 PM
> >> Subject: Re: [sdiy] electrosensitive devices
> >>
> >> >
> >> > Many suppliers, Mouser among them, put a
> blanket control system on all
> >> > semiconductors.  It's less expensive for them
> to put all semi's into the
> >> > costly nickel plated anti static bags than it
> is to concoct some large
> >> scale
> >> > sorting/segregation system, because it has to
> carry not only to the final
> >> > shipment, but through their entire
> warehousing/receiving system as well.
> >> > You can only imagine how hard it would be to
> assure that all static
> >> > sensitive parts, and only those parts, received
> special handling
> >> procedures,
> >> > are kept in a separate stores locations, etc.
> >> >
> >> > So,  if you are unsure which are and are not
> problematic for static, as
> >> > impractical as this may be, the best solution
> would be to carry out their
> >> > system in your lab and for you to treat
> everything as static sensitive as
> >> > well.   Yeah, I know...a drag.
> >> >
> >> > Problem is, and this came up a few months
> ago...99.99999999 to the tenth %
> >> > of the failures from the initial static
> discharge is not catastrophic.  It
> >> > merely degrades the part so it will lean
> towards infant mortality
> >> somewhere
> >> > down the road.  And when it does, it's hard to
> determine if ESD was the
> >> > cause unless you pop the top off and have a
> look under an extremely
> >> powerful
> >> > microscope. Even more impractical in my book.
> >> >
> >> > Two general rules of thumb will help you out a
> lot:
> >> >
> >> > 1)  Treat static like a virus and take the
> necessary precautions to keep
> >> it
> >> > from spreading.
> >> >
> >> > 2)  Get your hands around which parts are and
> are not susceptible and make
> >> > damn sure you at least keep them in foam when
> not in boards and wear a
> >> > ground strap when inserting them or when
> handling a board that has them
> >> > inserted, even if you are planning of fooling
> with those parts directly at
> >> > the time.
> >> >
> >> > I worked for a company (Western Digital) whose
> first products were
> >> > controller LSI chips.  This is what they
> started off doing and what put
> >> them
> >> > on the map. This was years before they
> purchased the Tandon hard drive
> >> > division. You have no idea what you have to go
> through to create a truly
> >> > static free environment.  We're talking heels
> straps, nickel faraday bags,
> >> > heel straps, wrist wraps, conductive booties,
> grounded forklifts, grounded
> >> > storage racks, grounded soldering irons, air
> ionizers, conductive mats,
> >> > anitstatic spraying of work benches - it's a
> complete mess.
> >> >
> >> > hope this helps - remember, it's not only 4000
> series CMOS you have to
> >> worry
> >> > about!
> >> >
> >> > Peter
> >> >
> >> >
> >> >
> >
> >--
> > -Jim
> >------------------------------------------------
> >* Visit:http://www.silcom.com/~patchell/
> >*-----------------------------------------------
> >* Come to the Pacific Southwest DIY Meet
> >* April 12, 2003 10am-5pm
> >* Santa Barbara, CA
> >* http://www.silcom.com/~patchell/synthdiymeet.html
> >* for details
> >*-----------------------------------------------
> >
> >
> 
>
=========================================================
>  
> - A smoking gun is one that's already been fired.
> - That which gets rewarded, gets done.
> - What good are laws that only lawyers understand?
> - Government: The other religion.
> - The media's credibility should always be
> questioned.
> 
> "When you see a rattlesnake poised to strike, you do
> not 
> wait until he has struck before you crush him." 
>   -- FDR
> 
> -- Scott Gravenhorst | LegoManiac / Lego Trains /
> RIS 1.5
> -- Linux Rex         | RedWebMail by RedStarWare
> -- FatMan: home1.gte.net/res0658s/FatMan/
> -- NonFatMan: home1.gte.net/res0658s/electronics/
> 


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