Author Topic: Episode suggestion: ESD is a myth  (Read 10135 times)

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Offline stevenhoneyman

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Episode suggestion: ESD is a myth
« on: July 20, 2015, 04:45:46 am »
There's plenty of people that never have and never will wear an antistatic wrist strap and can truthfully say they've worked with electronics/computers for X years and not broken anything, and I've never heard of a case of someone destroying parts accidently... but it's (obviously?) a real issue. Or maybe it's all just because some guy that worked in a Van de Graaff generator factory once had a component fail!

I think an episode dedicated to destroying a bunch of stuff with/without cheating would be interesting, and useful in demonstrating this. E.g. a quick breadboard test rig, bag of 555 timers/MCUs/whatever is cheap, then zap 'em after running around on carpet etc. With and without the wrist strap. I'm sure there's some more scientific way it could be approached as well, but until I see/experience a component failing due to ESD in an 'everyday' scenario, I'll always have my doubts.
 

Offline AndyC_772

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Re: Episode suggestion: ESD is a myth
« Reply #1 on: July 20, 2015, 05:15:26 am »
See here: http://www.eevblog.com/forum/beginners/esd-confirmed-kills/

And: <copy... paste... >


    ESD is a subject which is very poorly understood, even in the electronics industry where people should know better. Spare me a few minutes and I'll clear up a few misunderstandings that'll hopefully save you an expensive repair bill one day.

    First off, a few things you may already know about ESD:

    - Your DRAM is designed to work off 2.5V or less. Walking across a carpet can generate voltages in the order of 5,000V or more.

    - Rubbing two insulators together (eg. two layers of clothing) causes static electricity to be generated, by transferring electrons from the surface of one to the surface of the other

    - Static electricity that's just sitting there on the surface of an insulator isn't doing any harm. What causes damage is when that electricity is suddenly allowed to flow from one place to another via a conductive path. At the moment the conductive path is formed, the instantaneous current can be huge, and if your SSD (Static Sensitive Device - could be a DRAM module, CPU, motherboard - anything with exposed electronic components) is in that path, it can be damaged.

    - The discharge current causes a heating effect, just like when you connect the mains to an electric fire. Too much heat in a small device burns it out, it's that simple. The smaller the device - a transistor, for example - the more sensitive it will be to ESD damage.

    And a few things you probably DIDN'T know:

    - You DO NOT have to actually touch a Static Sensitive Device (SSD) such as a DRAM module in order to damage it. Merely passing your hand near it can be enough.

    - An ESD event can be strong enough to cause damage well below the threshold where you'll feel it - so you can destroy a device without even knowing it.

    - A device damaged by ESD DOES NOT necessarily stop working straight away, but its performance and lifetime can be drastically reduced. So, just because you put a machine together and it seems to work DOESN'T mean you've got away with it.

    - An SSD enclosed within a conductive anti-static bag is NOT completely immune to ESD damage, because although it's protected from electric fields, it's not protected at all from magnetic fields. A spark outside the bag causes a rapidly changing magnetic field, which can induce a current in any conductor inside the bag. (Think: that's how a generator works!)

    - the correct way to package an SSD is to put it within a conductive bag, and then to package that bag in a reasonable thickness of 'pink' bubble wrap or other packaging. The bag protects against electric fields, and the pink material provides enough physical space around the SSD that large magnetic fields (from sparks) can't be generated physically close enough to cause damage.

    - 'pink' packaging material is coloured that way by the manufacturer to indicate that it's made so that rubbing against it doesn't produce a charge. It is NOT conductive and it does NOT protect equipment from electric or magnetic fields. It is, however, the correct material to use to package SSDs that are already enclosed in conductive bags.

    - the pink colour is just an identifier. Retail boxed CPUs, for example, come in clear plastic because it looks nice, but that's OK - Intel & co know what they're doing.

    Be aware, though: an awful lot of PC component vendors DO NOT know the correct way to package an SSD. If you order a component, such as a CPU or memory module, and it's not correctly packaged, you'd be within your rights to send it back - IMHO, of course

    So, with all that in mind, what can you do to protect your equipment?

    In order to damage a component, you need a potential difference between the component itself and the thing you're going to touch it with. No PD = no current = no damage.

    So, normal practise in an electronic assembly plant is to ensure that everything is at the same potential all the time, and that means:

    - everything is conductive: bench, floor, tools, lab coat, even the waste paper bin. Unnecessary insulating materials (crisp packets, coffee cups etc) are banned from assembly areas.

    - everything conductive is grounded - NOT because there's anything 'magic' about ground, but that it ensures everything in the plant is at the SAME potential as everything else.

    - conductive materials used still have some resistance - they're not made of good conductors like copper and aluminium, but instead they use carbon loaded rubber or plastics. This ensures that when a potential difference does exist, the current involved is small and safe. Charge leaks away relatively slowly rather than suddenly.

    These basic precautions mean that everything the SSD's are likely to touch are at the same potential; no difference in potential = no current = no damage.

    So, assuming you don't have all that kit, what can you do to protect your equipment?

    - borrow the correct equipment! There really is no substitute for a dissipative bench mat and a wrist strap. Really! If your PC packs up in 6 months' time and you didn't use the proper equipment, you only have yourself to blame.

    ...but if that's simply not possible...

    - on a desktop PC, DO plug it into the mains, but turn off the power at the wall - you only want the earth connection. (Disclaimer: safety, safety, safety!!! If you're not absolutely 100% sure about the implications of this, get someone else to upgrade your PC for you! I am NOT RESPONSIBLE for anything YOU CHOOSE to do with your PC, REGARDLESS of whether YOU CHOOSE to treat my comments as advice or instructions!).

    - don't wear nylon or other synthetic fabrics - wear cotton instead. Or do the upgrade naked if that's your thing! But whatever you do, don't pull a sweater off over your head and THEN grab your shiny new DRAM module. All those little clicks you heard when you pulled the sweater off were ESD events - you're now charged up to 10,000 volts and your DRAM is doomed/

    - touch the EARTHED bare metal case of your PC.

    - touch the silver or black bag that your DRAM comes in to the bare metal case of your PC as well. There's no point in you being earthed if the SSD is charged up to 10,000V when you get it.

    - The moment you first touch the SSD after opening the conductive bag is the moment at which you're most likely to damage it, because you don't know what potential it's at. Get this into your head! A proper wrist strap contains a 1MOhm resistor to limit the current that'll inevitably flow through your shiny new DRAM when you first touch it. If you had a proper wrist strap on now, you wouldn't be about to risk blowing it up. Now is the time to decide NOT to open the bag today, and to pick up a wrist strap for a few quid off Ebay.

    - Remove the module from its bag and install into your PC. Try to maintain a finger or elbow in contact with the chassis of your PC at all times, it only takes a moment to 'recharge' once you let go!

    - Reassemble your PC and test.

    Finally, be aware that there's some scarily bad misinformation around about ESD. From this very thread:

    - "It doesn't matter, I've never had a problem" - see above. You can damage a module without realising it, and the damage may not show up for months. Now you know that this 'latent damage' can occur, you'll be in a better position to put 2+2 together when your PC 'inexplicably' packs up next year.

    - "Touch a metal object" - pointless. You need to ensure that you, your PC and the component you're installing are all at the same potential. If it's plugged in then your PC is at earth potential, so if you touch a metal water pipe (something which is connected to earth and, therefore, at the same potential), then that's good. But touching a door handle just makes you look stupid.

    - "Latex gloves" / "rubber" - WTF?! You're not trying to protect it from some biological infection - latex is an insulator and can therefore hold a charge. It's probably the worst thing you could possibly do from an ESD point of view. (Sometimes workers in a clean room use them to avoid contamination, but that's not the problem in this case).

    - "One hand in the back pocket" - is a good rule for personal safety if you're working on live equipment, because if you touch a live conductor it helps prevent current from passing through your chest. But your PC is switched off at the wall. Right answer to the wrong question. Ditto for insulating boots - workers in ESD protected areas wear conductive heel straps, and NEVER work directly on live equipment.

    - "Switch on after removing the battery to discharge the equipment" - wrong again. This has nothing to do with ESD, it's to ensure that the power supply caps in the PC have drained. All you need do is wait 10 seconds after switching off and you'll be fine. This has nothing to do with static.

    Hope that helps!!

    Andy.
     

 
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Offline AF6LJ

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Re: Episode suggestion: ESD is a myth
« Reply #2 on: July 20, 2015, 05:29:52 am »
I use to be an ESD denier, it took an assembler walking across the floor with plastic shoes, wearing pantyhose and handing me a VCO I hand tuned (spent ten hours doing so). The spark from her to me and my grounded chair and cotton cloths put an end to most of that ten hours of work.
A failure report for QA
Authorization to rework
De-Potting the VCO,
Replacing the burned open varicap diode.
Inspection
Retuning the VCO...
An operational test over temperature to make sure the VCO drift, deviation sensitivity and power output were all still in spec....
Inspection
Re-potting the VCO.
Finishing my part of the failure report, send to my QE for final disposition...
One day later I am back to where I was the day before.
The VCO sent back to top assembly to be mated with the remainder of the power train.

Three months later the transmitter line was shut down for ESD refit and education for one day. 


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Offline stevenhoneyman

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Re: Episode suggestion: ESD is a myth
« Reply #3 on: July 20, 2015, 05:37:46 am »
I use to be an ESD denier, it took an assembler walking across the floor with plastic shoes, wearing pantyhose and handing me a VCO I hand tuned (spent ten hours doing so). The spark from her to me and my grounded chair and cotton cloths put an end to most of that ten hours of work.
A failure report for QA
Authorization to rework
De-Potting the VCO,
Replacing the burned open varicap diode.
Inspection
Retuning the VCO...
An operational test over temperature to make sure the VCO drift, deviation sensitivity and power output were all still in spec....
Inspection
Re-potting the VCO.
Finishing my part of the failure report, send to my QE for final disposition...
One day later I am back to where I was the day before.
The VCO sent back to top assembly to be mated with the remainder of the power train.

Three months later the transmitter line was shut down for ESD refit and education for one day.

Result :-+

See here: http://www.eevblog.com/forum/beginners/esd-confirmed-kills/

It's an interesting read, although a lot in common with the other info out there (as you'd expect). What it's lacking though, and the reason for my episode suggestion is any repeatable proof. The software guys handed you some broken boards, how can you be sure that ESD was to blame, and not a moisture damaged component or faulty power supply they connected it up to (for example)?That's the type of thing I was thinking could be settled once and for all in an episode!

"Look, flashing LED"
*run around room*
*pick up the 555 timer*
"Look, it died!"

Demonstrating this in an eevblog video should/might end doubts people have.
 

Offline Deathwish

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Re: Episode suggestion: ESD is a myth
« Reply #4 on: July 20, 2015, 05:41:33 am »
I am too mean to buy real ESD earth plugs for the mains, I use a UK plug with the L/N pins removed, solder a 1M resistor to a length of wire and screw it to the fuse connector and the other end of the resistor to the earth pin, fix the lead through the strain strap and let it hang out the plug , either solder a loop on the end to fix a croc clip to for your regular ESD wrist lead or fix a regular cupboard bar handle under the bench and fix all your leads to that. cheap enough.
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Offline stevenhoneyman

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Re: Episode suggestion: ESD is a myth
« Reply #5 on: July 20, 2015, 05:45:23 am »
I've just found ep 247, might have been done already... I'll go watch it and see.
 

Offline AF6LJ

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Re: Episode suggestion: ESD is a myth
« Reply #6 on: July 20, 2015, 05:54:47 am »
No doubt ESD gets the blame for a lot of poorly diagnosed failures, but at what point does failure analysis our weigh its value?
In the example sited above you really don't have the money to do a conclusive failure analysis.
Not the same as manufacturing gear for the aerospace industry where when a failure pattern begins to develop a few killobucks spent on good failure analysis can save tens of millions, and maybe a contract or two.
Repairing a PC that can be replaced for a few hundred dollars, labor is the most costly component. I have worked in aerospace where an S-Band power transistor cost two weeks worth my wages, trust me when you blow two of these hand tuning a 40W S-Band PA (this was a couple of decades ago) they start asking questions with the intent of shutting down a line to get to the bottom of the problem.

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Offline Alphatronique

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Re: Episode suggestion: ESD is a myth
« Reply #7 on: July 20, 2015, 06:27:12 am »
it just like to me that ESD like most time as mafia Protection racket  ,listen some ESD specialist and you end up whit ESD safe toilet paper    :palm:

it also kind of stuff that ING like to blame to when it no find better answer for a defect  :-DD or a bad design...

look carefully all electronic assembler ,you will notice almost never have ESD floor or have whist trap or else ,that plain normal since it handel part in REEL and PCB by it edge 
that was the key ,so NOT put your finger on any IC pin ,keep humidity high and monitor ESD on the shop ,and if do rework do it in ESD safe bench and tool

one funny thing is that when PCB was on the Reflow Oven it surrounded by forced circulating hot air  so very dry and Very static prone  :scared:  :popcorn:
some oven have negative ion generator on cooling Zone ,that nice HV arc strait to air under the PCB   |O

a good example i have make  ESD floor on my facility  ,ESD gourou what to sell me ESD tile for 10$ per scare foot !!!  and tile have same conductivity that a plain concrete Floor
have end-up whit Epoxie paint made for munition facility and that one was truly conductive not the Disipative stuff that have Giga-ohm resistivity that cost arm and a leg

after have play whit ESD meter for some time have happy to find that most usually stuff was already static safe ,but ESD mafia still ask for buy stuff that ESD logo on it  and big price tag ....


as final note 99% of the small computer repair shop have absolutely no idea about ESD or and protection on any kind  and manipulate bare hand CPU and DRAM stick
did every home computer handle by that small shop fail mysteriously after after fix ?   
most offer warranty on computer in assemble and sold  ,did it all back-rout later since ESD damage warranty repair ??

ESD was just like lead-free solder "issue" it greatly over exaggerated  ,yes must be carefully but gourou like to create itself full time job based on it fear  O0
« Last Edit: July 20, 2015, 06:38:41 am by Alphatronique »
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Online mikeselectricstuff

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Re: Episode suggestion: ESD is a myth
« Reply #8 on: July 20, 2015, 06:33:18 am »
Quote
    - An SSD enclosed within a conductive anti-static bag is NOT completely immune to ESD damage, because although it's protected from electric fields, it's not protected at all from magnetic fields. A spark outside the bag causes a rapidly changing magnetic field, which can induce a current in any conductor inside the bag. (Think: that's how a generator works!)
I can't believe that's plausible. Inverse square law for starters, combined with tiny loop area inside any device to pick up sufficient energy to cause damage. 
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Online coppice

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Re: Episode suggestion: ESD is a myth
« Reply #9 on: July 20, 2015, 06:58:19 am »
If you live in a very humid place ESD precautions might be a waste of time for you. If the humidity is moderate to low, and you don't take reasonable case about static on a production line, failure rates at the product test stage can be horrendous.
 
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Offline Corporate666

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Re: Episode suggestion: ESD is a myth
« Reply #10 on: July 20, 2015, 05:02:18 pm »
ESD is real, of course... we can measure it, we can test for it, we can reproduce the results.

But I think it is massively over-inflated beyond it's real dangers.  I have never used an ESD strap, and in 15+ years of working in electronics and in all my life, I've never ever damaged something from ESD to my knowledge.

I've also not had any unexplained failures that could be chalked up to ESD.  I think ESD damage is probably like turning your engine off when you refuel.  Yeah, it makes sense... and yeah, some serious accidents have occurred from ignoring the advice, but the chances of anything going wrong are statistically miniscule.
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Online mikeselectricstuff

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Re: Episode suggestion: ESD is a myth
« Reply #11 on: July 20, 2015, 05:45:28 pm »
    - Your DRAM is designed to work off 2.5V or less. Walking across a carpet can generate voltages in the order of 5,000V or more.
The voltage not the issue, it's about potential discharge current. The 5kv figure is meaningless without reference to the capacitance it's stored on.
It's all about the D, not the ES

It basically boils down to risk vs. consequences. In a lab/development environment, it's usually not a huge issue, as anyone working with semiconductors will understand the risks and know not to do stupid things like wear synthetic clothes. The cost consequences of ESD damage are also relatively low at this stage
However in  a production environment, many of the staff handling devices and boards will not have sufficient technical knowledge(and may care less).
The potential costs of  damage that doesn't surface til a product is much further down the production line, or even in the field are orders of magnitude higher, and difficult to trace back to a root cause.
Therefore imposing some rules that have a high probability of avoiding risks is a very pragmatic way to reduce risks. It may be the case that some precautions are redundant, but the risks of getting it wrong will often outweigh any cost savings.

The only ESD precautions I've ever taken are to install anti-static carpet in the workshop, and touch earth before putting an expensive CPU in a motherboard. I've blown stuff up in many interesting and dramatic ways but ESD hasn't been one of them. 
« Last Edit: July 20, 2015, 05:47:25 pm by mikeselectricstuff »
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Offline firewalker

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Re: Episode suggestion: ESD is a myth
« Reply #12 on: July 20, 2015, 05:51:27 pm »
I believe damaging ESD events curve goes down as far the product is from the manufacturing stage. For a finished board with proper design it would be really strange to systematically fail due ESD.

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Offline Alphatronique

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Re: Episode suggestion: ESD is a myth
« Reply #13 on: July 20, 2015, 11:46:20 pm »
one of common guilty that blamed to be ESD in manufacturing was popcorning

customer order part for it project made 2-3 prototype for test it then later start the production ,then find production board fail when prototype worked  and blame ESD in assembly shop

what happen in reality was during delay from prototype to  production humidity migrate into IC epoxy body ,then on reflow that humidity simply "explode" like pop-corn
that generate all king of trouble from plain DEAD IC to intermittent issue ,so very similar to ESD damage   
simple cure was store part before assembly for 24H in sealed container filled whit  desiccant Bag  ,that bag may  reuse to infinity by "reflow' it

and not forgot that in assembly shop no one actually toutch part  ,that come in reel  that ESD if need  the pick place handel it no human , one pick place finish  no one tout the part or trace
board was handel by it edge 9 Before V-score border was remove)  ,same for reflow and wash   ,only time a part may touch it during TEST or rework  ,so very unlikely that damage occur at that stage
most of time ESD was check  as last option  ,even if some Gourou point it first  and miss the point ...
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Offline Neilm

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Re: Episode suggestion: ESD is a myth
« Reply #14 on: July 21, 2015, 05:18:21 am »
Some time ago, one of the products I had worked on started to get a lot of warranty returns - all for the same fault. We spent ages trying to find the issue - they all worked when they left the factory but failed within about 6 months.

We ended going the the chip suppliers, who did all sorts of tests on the failed chip (including X-Rays) and concluded that there was some ESD damage. After a lot of investigation, it turned out that our supplier had re-reeled the devices and the glue they had used to hold the tape on the carrier caused a huge potential when removed. This built up and eventually discharged damaging the chip.

Ironically, during the time taken to do these investigations the problem seemed to go away - we believed that as we had started using more of the chips we bought larger quantities and the supplier stopped re-reeling.
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Offline AF6LJ

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Re: Episode suggestion: ESD is a myth
« Reply #15 on: July 21, 2015, 10:40:34 am »
I would have been in that supplier's face so fast  :box:  ; >:(
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Online Howardlong

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Re: Episode suggestion: ESD is a myth
« Reply #16 on: July 21, 2015, 11:58:46 am »
If I am doing some work at a place that dictates the use of varying degrees of ESD protection, I will universally abide by the local instruction, irrespective of whether I think it's poppycock or not.

In my situation if I have to dress up it is typically in a clean room and the stuff I'm working is on stuff that will be going into the vacuum of space. Strapping up, one way or another, is the norm.

Although my own experiences suggest that ESD itself is overplayed, this is as much to do with the psychology of taking care as much as anything else. Once you've donned your special shoe covers, hair nets, nitrile gloves and lab coats (or whatever is dictated in the given environment, ask three different clean room managers you'll get three different answers), you feel a bit special, you take extra care. A bit like going out for a special occasion, you dress up, and behave appropriately, well most of the time anyway.
 

Online CatalinaWOW

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Re: Episode suggestion: ESD is a myth
« Reply #17 on: July 21, 2015, 01:49:27 pm »
Worked in aerospace where we spent the money to find out what caused failures.  De-lidded components, did photomicrographs, stripped metallization and so on.  Often found that there was a little crater in the chip.  So "something" caused a localized rapid heating event.  Most events with supply voltages supply heat slowly enough that when a crater is generated it is large.  So the something was a short high power event.  ESD can never be proved in a case like this, but it is the most likely and one of the few possible causes.

More interesting were the times when craters or burns in the metallization were found that did not prevent function of the part.  The most common case was in the wiring for or the actual ESD protection diodes themselves.  So the ESD protection diodes had done the job, and since they are not directly involved in circuit operation everything still functioned.  But the protection was now gone, so the next event would get something else.  Other cases included metallizations that still had a conductive path, but were significantly narrowed.  Not good for the life of the component, but maybe OK, and would fall in the "I've never had an ESD failure bucket.  In other cases a device or subcircuit had been destroyed, but that function either wasn't used, or wasn't obviously necessary for circuit function.  The circuit might have more bias current, or higher crossover distortion or some other factor which wouldn't be noticed unless your circuit depended on that element of the part performance AND you tested the resulting performance.  These cases would also go in the "I've never had an ESD failure bucket".

The bottom line.  If you care whether your device works next week or next year, and if your environment does not naturally prevent ESD then take ESD precautions.  If you never get zapped as you slide out of your car or touch a doorknob you may not need to do anything special.
 

Offline HAMERMAN409

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Re: Episode suggestion: ESD is a myth
« Reply #18 on: September 16, 2017, 04:22:25 am »
For me it has been location, location, location. I have always worked in places where we take the issue quite seriously and except for one instance it was never a problem. At a previous job where the combination of rolling lab chairs and vinyl floor tiles made it a very real problem. The mistake here was that the tiles were standard warehouse style tiles with no concern for anti-static. You could sit at a bench, roll back one foot and then roll back to the bench and draw a spark pretty easily. That building had undergone many reconfigurations through the years so using the incorrect tiles was just a leftover from when that particular area was used for something else but since it was a test lab and not a production area they left it that way and we just had to be extra careful. 
 

Offline Cerebus

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Re: Episode suggestion: ESD is a myth
« Reply #19 on: September 16, 2017, 05:05:20 am »
... it turned out that our supplier had re-reeled the devices and the glue they had used to hold the tape on the carrier caused a huge potential when removed. This built up and eventually discharged damaging the chip.

An amusing thing to do when it's dark and you're bored.

Get a reel of sellotape. Go into a dark room - proper pitch black. Give your eyes five minutes to adjust to the dark. While watching, pull six inches of tape off the reel at a normal speed. Watch the miniature lightning as the tape pulls off the reel.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
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Offline Mr. Scram

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Re: Episode suggestion: ESD is a myth
« Reply #20 on: September 29, 2017, 01:43:21 am »
An amusing thing to do when it's dark and you're bored.

Get a reel of sellotape. Go into a dark room - proper pitch black. Give your eyes five minutes to adjust to the dark. While watching, pull six inches of tape off the reel at a normal speed. Watch the miniature lightning as the tape pulls off the reel.
Wait for collegue to suddenly open door and find you with a piece of tape, ready to attack. Explain to boss.
 

Online wraper

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Re: Episode suggestion: ESD is a myth
« Reply #21 on: September 29, 2017, 02:58:32 am »
A long rime ago I had an argument with my fellow worker when I worked in mobile phone repair shop. We made some rearrangements at work and I put ESD mats on my new workplace and correctly wired them, while most of another desks had ESD mats but were not wired. He said why I would bother, nobody ever seen failure due to ESD anyway. I then asked him: "how many times you disassembled some phone and it died after that?" He then shut up. I don't think there were that many cases I can certainly say I killed something with ESD, but there were a few that I'm pretty sure about and I've seen an actual spark a few times which resulted in dead component. Once I moved expensive 2 years old Intel CPU from one motherboard to another, and it died next day. I cannot think anything other than ESD damage, as replacement CPU worked 2 years since then on the same motherboard.
 

Offline AlienRelics

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Re: Episode suggestion: ESD is a myth
« Reply #22 on: October 04, 2017, 06:09:49 am »
Sainsmart sent me two 3.2 inch TFT displays with the pins stuck in white foam, packed in clear ziploc bags. Both were damaged, the displays had lines and would not work correctly. They also shipped four 2.4GHz transceivers with the pins stuck in white packing peanuts, held on with plain clear packing tape and stuck in clear ziploc bags.

None of them worked properly. An email conversation with someone at Sainsmart revealed that their shipping department seems to be entirely ignorant of ESD and protection against ESD.

I've had a variety of sellers on Amazon ship with no ESD protection, or just in pink bags as if that provided protection. I got tired of testing and finding damage, now I just immediately file a return if they aren't in silvery gray or black ESD shielding bags.
 

Offline timgiles

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Re: Episode suggestion: ESD is a myth
« Reply #23 on: November 29, 2017, 07:26:05 am »
I built and repaired computers growing up (now 40) in the UK and not once did I wear anything to strop me zapping the bios, memory etc.. My home was fully carpeted in the SE of England.

Moved to mid/north sweden 7 years ago. My fantastic Sony Vaio laptop, I zapped 3 motherboards in 2 years :-( Since then, never work without one either PCs/laptops or electronics. My drier here in Umeå, colder. Not really sure what is worse / better.
 

Online coppice

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Re: Episode suggestion: ESD is a myth
« Reply #24 on: November 29, 2017, 07:36:37 am »
I built and repaired computers growing up (now 40) in the UK and not once did I wear anything to strop me zapping the bios, memory etc.. My home was fully carpeted in the SE of England.

Moved to mid/north sweden 7 years ago. My fantastic Sony Vaio laptop, I zapped 3 motherboards in 2 years :-( Since then, never work without one either PCs/laptops or electronics. My drier here in Umeå, colder. Not really sure what is worse / better.
In the 70s and 80s there were still lots of electronics production lines in SE England, and they had lots of issues with static damage in the summer, until they started to effectively control it. The winter is damp enough that the aren't so many natural problems there. However, its easy to create problems with inappropriate heating systems, that make the humidity plummet.
 


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