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When I'm handling an IC that is sensitive to ESD that comes packaged in an antistatic bag, do I nullify my ESD protection procedures if I peel back the cut-tape and dump out the IC into a plastic cup instead of dumping it directly onto the surface of my ESD mat? Do I need to dump the IC out directly onto the surface of my ESD mat for it to equalize its static charge with me, my mat, and my soldering iron?

Assuming that the answer to the above is "yes", then does it make a difference if the pins of the IC touch the mat or not? I'm guessing that if you dump an IC onto a ESD mat and the pins never touch, then the internal conduction pathways of the IC are still statically charged relative to my local earth ground, and that when I plop it onto my PCB for soldering the ground plane of the PCB has enough stray capacitance to allow an ESD discharge from the IC to the ground plane of the PCB (which has been earth-ground equalized prior to this by way of me touching an exposed ground plane pin ).

Is this a thing? Do I need to worry about the stray capacitance of the PCB ground plane and differential static voltage between the PCB ground plane and IC being placed on it?

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  • \$\begingroup\$ Just leave the bag on the mat for a while, and you are good to go. \$\endgroup\$ – Vladimir Cravero Aug 2 '17 at 21:54
  • \$\begingroup\$ If you equalize your finger charge to mat or bag or ESD container , then you are less likely to have a difference voltage to discharge harmful current thru any path via the pins . A 1M mat connection to wrist strap makes it easy to do this all the time. Handling a PCB by the earth or Vdd pin makes easier to protect as well. \$\endgroup\$ – Sunnyskyguy EE75 Aug 3 '17 at 4:58
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Trust me, it is totally fine to dump it on to the ESD mat. Think about what the antistatic bag does: it keeps any stray charge from going through the contents, but still can have a slight charge on its exterior.

So, if you are touching your mat with one hand and holding the open antistatic bag in the other hand, then there should be zero potential difference between the bag and the mat. The are neutral to each other because they share a common ground - you.

Once they are neutral to each other, then the contents of the bag are also neutral and completely safe to dumb onto the mat. Just make sure you are touching the mat with one hand and the bag with the other hand when you dump your stuff onto the mat.

I say all this as a person who is overly cautious of harmful static.

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Is this an antistatic bag or a static shielding bag? Sensitive components should never be shipped in a poly bag. If that's the case you should be contacting whoever packaged it because it could already be compromised. Antistatic or even dissipative bags don't prevent charges from penetrating to the interior, static shielding bags do.

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