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Recently I ordered 100x IRLZ44N power MOSFETs through an eBay vendor based in the US. Today I received the package, and they were simply wrapped in bubble wrap and taped shut. This is obviously not proper packaging for ESD-sensitive parts like MOSFETs.

Should I immediately return the parts? Or should I try some and see if they work?

Thanks for advice. Below is an image of what the shipment looked like. On the left are the packages in question, and on the right is what I would expect for ESD-sensitive device shipping.

enter image description here

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    \$\begingroup\$ Up to you, there's a chance that probably some or even most of them will work, but it's a gamble. If they were cheap enough and you know how to test them maybe it's not a bad deal. I personally would never buy components from eBay, but to each their own. \$\endgroup\$
    – John D
    Commented Jul 23, 2017 at 3:16
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    \$\begingroup\$ Well just because some shipped in an ESD bag doesn't mean the supply chain up to that point is ESD compliant, so its still a gamble with the parts in an ESD bag. \$\endgroup\$
    – sstobbe
    Commented Jul 23, 2017 at 3:32
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    \$\begingroup\$ @sstobbe If you buy from a reputable distributor or direct from a manufacturer you can be sure that packaging is ESD compliant. With EBay, not so much. \$\endgroup\$
    – John D
    Commented Jul 23, 2017 at 3:44
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    \$\begingroup\$ @JohnD Exactly! With Ebay all bets are off. Even if the parts come in an ESD bag they may well have been hand picked from a bucket dumped out on the carpet. \$\endgroup\$
    – sstobbe
    Commented Jul 23, 2017 at 3:49
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    \$\begingroup\$ No, I would not buy any electronic components from eBay. I would stick to the reputable distributors like Digi-Key, etc. However, I'm not a hobbyist and I can understand why some people might want to save some money buy being from eBay. \$\endgroup\$
    – John D
    Commented Jul 23, 2017 at 4:13

3 Answers 3

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Bad news. Beside of catastrophic failures, which can be detected by normal inspection, ESD damage to electronic components can lead also to latent defects, which cannot. Partially degraded components may randomly shorten the lifetime of equipments, do not use them in critical applications.

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You could test all the mosfets, but I suspect that none of them are damaged. I have received IRLB8743 mosfets in a plastic bag many times before, and have never discovered a dud mosfet in the batch.

Test circuit:

schematic

simulate this circuit – Schematic created using CircuitLab

The LED should be on, and should go off when the button is pressed. If the mosfet passes this test, then it is probably OK.

[EDIT] I recently received some IRF3205s in a plastic bag and one of them was dead on arrival. Don't trust components in a plain plastic bag unless you test them.

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  • \$\begingroup\$ Thanks for the fast response. Just wired up a similar test circuit (gate tied to ground, switch connected to VCC) and all the ones I've tested so far (around 25) are working. I guess I won't return them. \$\endgroup\$ Commented Jul 23, 2017 at 3:42
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    \$\begingroup\$ I've had them supplied both ways and not found any failures in the non-ESD ones. However, as has been noted on other discussions here, I live in England, a notoriously damp country. I suspect there would be a failure rate in drier climes. \$\endgroup\$
    – Ian Bland
    Commented Jul 23, 2017 at 10:57
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Yes you should return them, most mosfet gates are nm thick and are some of the thinnest parts of a fet. Because of this it doesn't take much to blow through enter image description here
Source: https://www.researchgate.net/publication/312332929_Impact_of_back_plane_doping_on_RF_performance_of_FD-SOI_transistor/figures?lo=1

Here is a picture of what can happen to a fet with an ESD discharge.

enter image description here Source: TI ESD falures ssya010 (a good read)

Most modern FETs come with some kind of ESD protection, some older fets without protection could be destroyed by waving your hand over them.

The problem with ESD is you don't know what will happen, it could fail after you put it on the board, or months from now. If you know a device has been exposed to an ESD field all bets are off, you don't know if the device is damaged or not, so get parts that you know are good from the manufacturer.

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