For hand-soldering, I don't see any need to worry about the moisture content of the ICs. That's more of an issue for oven reflow, where humidity in the IC packages can cause the package to crack during soldering.
If the ICs are still in their sealed bag with desiccant and humidity detector card showing all blue circles, I'd be even less concerned.
Tom
If the ICs are still in their sealed bag with desiccant and humidity detector card showing all blue circles, I'd be even less concerned.
Tom
The relevant JEDEC standard for baking is JEDEC J-STD-033B. Page 8 lists the baking times.
You can download the standard from JEDEC after registering or from Digikey without registering: JEDEC J-STD-033B Standards - SCS | DigiKey
Also see TI's app note on the topic: http://www.ti.com/lit/an/snoa300a/snoa300a.pdf
Tom
You can download the standard from JEDEC after registering or from Digikey without registering: JEDEC J-STD-033B Standards - SCS | DigiKey
Also see TI's app note on the topic: http://www.ti.com/lit/an/snoa300a/snoa300a.pdf
Tom
Nope. Shelf life is a thing. See the docs I just linked to.
It's not like the components go bad. It's just that the packages (i.e. the plastic/ceramic that surrounds the IC, bond wires, and lead frame) will crack and damage the component if you attempt oven reflow with a package that has too much water absorbed in it.
Tom
An externally hosted image should be here but it was not working when we last tested it.
Thanks Tom. I have not even opened the bag, just got lost in my messy part boxes. Its just to had solder onto adapter and into amp phonostage, and tone
Sam
Leadbelly not sure of self life, not like a capacitor, not sure they can be stored too long
As well as the package moisture content mentioned above, lead solderability goes off with age
Different surface mount packages have different moisture sensitivity levels. It's sometimes frustrating to find the MSL rating, but it's usually defined somewhere in the data sheet or on the manufacturer's web site. Digikey usually lists a part's MSL on the product's page, and that can sometimes be a simple way to get the information. MSL 1 requires no special handling, but anything higher requires storage in a dry environment. Check the packaging when you get the parts - it will be correct, and will give you a window after the package was opened.
I'm sure that most here will know that epoxy package semis are not hermetically sealed. When I did design work for industry, finished boards all had to be tropicalized to help prevent ingress in both the boards and components. An opamp or similar would soon degrade living in a damp factory
If those parts have been baged then there's no problem.
If those parts have been baged then there's no problem.
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