Hi, I just bought some 555 timer ICs and when I opened them they smelled really bad, something like burnt plastic, I bought 555 timers before from other sellers and I never experienced anything like this. Right now I have them outside, airing out. So what is causing this bad smell, is it dangerous? It kind of smells dangerous.
Thank you.
Could be dangerous - all sorts of nasty chemicals used in plastics manufacturing.
I have a number of LED strips which came in plastic "Zip-loc" envelopes and - though I have not tried airing them out for any time - smell awful. I can even smell them when I open the storage bin!
So what should i do about it?
virtuos1:
So what should i do about it?
Your options are pretty simple. You can air things out or return to sender based on foul odor. As to what could it be? Could be anything. Do whatever you are comfortable with doing.
Ron
OK.
Thanks.
Would spraying Lysol on it short circuit anything.
I would not get carried away with Lysol. If they are really that bad just place them in a zip loc gallon bag with an open box of baking soda. The baking soda should draw the odors away and absorb them. Then too I doubt Lysol would hurt 555 timer chips. 
Ron
You can wash them with soap and water, of course just dry completely before use. Isopropyl Alcohol can be used to clean them as well.
OK. Thank you so much.
Look up close, are they new or used parts. There is a huge grey market for "pulls"... do you really want to use parts that may have been in a fire or running in some industrial box since 1978?
They look OK to me, though I don't know how to tell....
virtuos1:
They look OK to me, though I don't know how to tell....
Look closely at the pins and package with a strong magnifying glass or microscope. A used part will have slightly bent and distressed pins. A brand new DIP package pins are slightly angled outwards, they bend in slightly when placed in a socket. Also look for traces of solder from de-soldering. The package may have a little telltale dirt.
It is a 50 pack but I checked as much as I could and it looks OK, I left it outside for awhile and the smell disappeared.
Thanks for your help.
Just buy your parts from a reputable supplier paying more or deal with issues like this. Any reputable supplier would be happy to exchange or give you credit on a return. Hell if you sleep with dogs there is a good chance you will catch fleas.
Ron
Ron_Blain:
I would not get carried away with Lysol. If they are really that bad just place them in a zip loc gallon bag with an open box of baking soda. The baking soda should draw the odors away and absorb them.
But do not get baking soda on them as it is corrosive.
Dry powder fire extinguishers are not good for electronics - or cars!
Paul__B:
But do not get baking soda on them as it is corrosive.Dry powder fire extinguishers are not good for electronics - or cars!
Yeah, for the slow on uptake you place an open box of baking soda in a for example 1 Gallon zip loc bag with your parts, the operative word being with. You do not dump baking soda on your parts.
Ron
virtuos1:
Hi, I just bought some 555 timer ICs and when I opened them they smelled really bad, something like burnt plastic, I bought 555 timers before from other sellers and I never experienced anything like this. Right now I have them outside, airing out. So what is causing this bad smell, is it dangerous? It kind of smells dangerous.
Thank you.
Those look very obviously fake I'm afraid, the smooth black coating gives it away - they've been
sanded, painted black, and then printed, the smell is due to this. Real chips nearly all have a
textured surface which help to spot this.
In the last few years its got to the point that any chips from eBay are very likely to be fake/recycled, only
shop from reputable electronics stockists.
It’s hard to tell the fakes. Sometimes they burn off the markings and remark them... who knows. There are books on the subject. Only time they are actually counterfeit in my book for a design that everyone makes is when the die is a direct copy or when they mark fake Ti or other logos on them.
The 555 is an old chip and one many mfg make, no sense in counterfeiting it... they are less than $0.10 here and even less in China. The Atmel counterfeits we see are more lucrative.
Perhaps they skipped some cleaning step and the epoxy was exposed to stinkiness. If they work then all good.
Buyer beware, these chips with no documentation might be fine for hobby use, if they work, but should never be used for critical stuff
MarkT:
Those look very obviously fake I'm afraid, the smooth black coating gives it away - they've been
sanded, painted black, and then printed, the smell is due to this. Real chips nearly all have a
textured surface which help to spot this.In the last few years its got to the point that any chips from eBay are very likely to be fake/recycled, only
shop from reputable electronics stockists.
What is the difference between "real" and "fake"? If it works, it works.
virtuos1:
What is the difference between "real" and "fake"? If it works, it works.
Nothing for general hobby use. That said I would not want fake used in for example the control surface electronics of anything I fly on or that goes underwater like a submarine. I guess anything safety of life I prefer to know where the parts came from. Again, for hobby use not much so I guess to me it comes down to application.
Ron