What is "Lead-Free" meaning in IC Packages ?

[Oveis.Gharan]

Dear all EDABoard members,
Salaam
Is there anyone who could tell me what is the exact meaning of "lead-free packages"?
Why the manufacturers had used from lead (Pb) in packages before and what was Pb benefit in packages?
Is there any benefit for leaded packages to prefer to use in front of lead-free ones?

Thanks in advance.
Oveis

 

[yadavvlsi]

Lead free package means It doesn't contain lead. Lead is a heavy metal with atomic number 82. If ingested, lead is poisonous to animals, including humans. It damages the nervous system and causes brain disorders. Excessive lead also causes blood disorders in mammals.

https://en.wikipedia.org/wiki/Lead

 

[Tanmay Dash]

refer site https://www.maximintegrated.com/en/emmi/faq.cfm

 

[Gorgon]

To get electronics 'lead-free' is part of the EU RoHS directive: https://en.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive

That's why you see 'lead-free' together with 'RoHS-compliant' in data sheets.

 

[FvM]

The "lead-free" package qualification has a twofold meaning:

1. As said they don't contain lead, particularly no tin-lead solder alloy, either as pin surface coating or solder balls.

2. It can stand the elevated temperatures required for lead-free solder processing

The latter has turned out as the more problematic point.

 

[Ricardo_Electropepper]

Well, in practical purposes and for hobbyist, using a lead-free package or not doesn't matter much, its just that the lead-free package will take more heat whitout damage, but using lead-free tin over leaded tin then there's a big diference, it will be more dificult to solder with lead-free because it requires more heat aswell more skill and in the end it wont be so shiny (pretty, if that matters).
I have some more old-school coleagues that really hate to solder with lead-free, it will be ok once you get the hang of it(a lot of practive).

 

[ads-ee]

I think the worst problem with lead free RoHS solder is the issues with thermal cycling causing both tin whiskers and metal fatigue. . It's getting more apparent that RoHS solder is starting to result in reduced life expectancy of electronic products. Anyone heard of an Xbox 360 that suffers from RROD, well that just so happens to be a problem with cracked solder joints of the RoHS compliant GPU due to the severe thermal cycling that occurs in that system. There are a number of entrepreneurs on ebay that have home surface mount soldering stations that will reflow the GPU to fix them.

I for one never saw such a mortality rate when lead solder was used.

 

[Mattylad]

Being lead free also means that the expected life is far less, that dry joints will be more prominent in the future and that its generaly not going to last as long as its old lead free version.

But heck - this is what the powers that be tell us we must do.

 

[Ricardo_Electropepper]

Poison by lead will cause severe alucinations, remenber the mad cientists in the past ? Too much soldering with lead

 

[Audioguru]

I have a lifetime supply of excellent leaded solder. I never tried to solder with lead-free solder and I never will.

 

[chuckey]

Mad scientists syndrome was caused by mercury poisoning. Harry Patch AKA "The last Tommy" died at the age of 115 years, he was a plumber who worked with lead all his life. the front piece in the book shows him working with lead on the tower of University of Bristol in the 20s.
Frank

 

[Audioguru]

I have used leaded solder every day for about 56 years. My wife says that sometimes I am "mad as a hatter" (they used mercury, not lead) but I have never eaten lead so I think I am fine.

 

[Ricardo_Electropepper]

I do solder with lead-free and after a while you get use to it, im actually pretty good at it these days, also the final joint soldered is not as "pretty", it wont be so shiny has in leaded tin.
I think Audioguru should just move on, its not a big deal.