Can You Build Your Own Computer with Limited Knowledge of Electrical Circuits?

[Averagesupernova]

Electrostatic discharge is real and is not a myth. However, some parts are much more prone to it than others.

 

[Dngrsone]

Just my $0.02 about grounding, as a senior applications engineer for one of the largest semiconductor manufacturers in the world: it's no longer even important. Seriously.

With all due respect, I can't believe someone of your "stature" would say something like this. If ESD weren't that significant, then why is there an ESD Association who cites up to 97% loss to electrostatic damage in the factory and up to 70% loss at the user level? Why is there an entire industry built around controlling the effects of ESD, one of which has a list of http://www.evaluationengineering.com/archive/articles/1102esd.htm attributed by thirty different companies?

All chips made today are designed (and tested -- again and again) to withstand enormous electrostatic discharges without dying. They will degrade, meaning they become more and more susceptible to ESD with each exposure -- but one or two zaps almost certainly will not kill any modern IC.

This goes doubly for any IC already mounted to a printed circuit board; the traces themselves are covered with solder mask, and any connections exposed to the outside world are protected with resistors. You are one extremely unlucky engineer if you manage to fry a part on a PCB with your hands -- it honestly really just doesn't happen.

- Warren

Yes, modern circuits are as well protected as they can be made and still able to perform their primary function. However, encouraging users to test that protection by ignoring ESD safe practices is just wrong. That's tantamount to telling people who've been immunized against smallpox that they can play with the virus with no significant safeguards because they aren't likely to get sick.

 

[Pengwuino]

With all due respect, I can't believe someone of your "stature" would say something like this. If ESD weren't that significant, then why is there an ESD Association who cites up to 97% loss to electrostatic damage in the factory and up to 70% loss at the user level? Why is there an entire industry built around controlling the effects of ESD, one of which has a list of http://www.evaluationengineering.com/archive/articles/1102esd.htm attributed by thirty different companies?

Because what else is there to cause losses? I've had countless ESD's on my computer components and nothing has happened. I've even had a horrific discharge when i pulled the main ATX cable out without pulling the power supplies plug out. I saw a relatively large flash and the motherboard continued to run perfectly. I think your latter comment about an entire industry bent on controlling ESD is the answer to your initial question of how someone could think ESD isn't a problem. We don't feel its a problem precicely because there is that huge industry that has worked to make it a non-issue and has, in my own experiences, done a fantastic job at making it a non-issue.

 

[chroot]

97% loss to electrostatic damage in the factory

You are absolutely correct that ESD is a critical concern for fab and test operations which are working with bare parts.

Why is there an entire industry built around controlling the effects of ESD, one of which has a list of http://www.evaluationengineering.com/archive/articles/1102esd.htm attributed by thirty different companies?

As Pengwuino said, the ESD industry is what's responsible for the durability of today's products!

However, encouraging users to test that protection by ignoring ESD safe practices is just wrong.

I didn't encourage anyone to test the protection; I simply said that thorough grounding procedures are next to pointless on fully-assembled boards, complete with solder-mask and proper current-limiting resistors on all external contacts.

- Warren

 

[Dngrsone]

Well, I'm just saying that by stating that taking basic ESD precautions is not important is akin to condoning unsafe practices.

I'm in an unique position in that I don't have the luxury of working on modern electronics, and it's an uphill battle convincing both old-timers and their highly impressionable proteges that ESD is a significant hazard to our equipment, and I must encourage safe practices at all times in the hope that a few will actually use them... ESD is the primary reason why my mean time between failures is in triple digits (in hours) instead of five.

 

[Averagesupernova]

I wouldn't say that the ESD industry is responsible for 'bullet proof' products concerning ESD. The ESD industry I have in mind is responsible for products used to safely handle the parts. Grounding straps, conductive finishes, containers and so on...

The folks repsonsible for the 'bullet proof' products are those who design the ICs used in todays products. Protection diodes that can handle a fairly large discharge current and so-on. ESD damage can be very subtle. It can cause a leaky protection diode on the PIN of an IC for instance. I agree with Dngrsone on this. Just because you can zap your mother board and have no sign of damage, why take the chance? I also wouldn't count on any of the insulating coating (solder mask) on a PC board or interconnects helping at all against ESD.

However, just because you aren't wearing a grounding strap doesn't mean that you are a huge threat. There are other ways that the charge leaks off of your body.

 

[Dngrsone]

I also wouldn't count on any of the insulating coating (solder mask) on a PC board or interconnects helping at all against ESD.

The mask helps reduce the chance of EM-induced discharges.