magnetizable LED leads

[Bernhard Kuemel]

I noticed the leads of a 5 mm white LED were magnetizable. I thought
they were tinned copper, but that's obviously not the whole truth. What
are they made of?

 

[Spehro Pefhany]

I noticed the leads of a 5 mm white LED were magnetizable. I thought
they were tinned copper, but that's obviously not the whole truth. What
are they made of?

Sometimes they use steel (plated). Steel has much lower thermal
conductivity so it's not as good, but it is cheaper.


Best regards,
Spehro Pefhany

 

[Fred Abse]

I noticed the leads of a 5 mm white LED were magnetizable. I thought they
were tinned copper, but that's obviously not the whole truth. What are
they made of?

Tin plated steel.

Some manufacturers' IC lead frames are the same, also transistor leads.

 

[Weland]

Tin plated steel.

Some manufacturers' IC lead frames are the same, also transistor leads.

Is there some hidden legitimate reason to this other than price? I was
under the impression that steel is not a very good option due to its
thermal properties.

 

[Bernhard Kuemel]

Sometimes they use steel (plated). Steel has much lower thermal
conductivity so it's not as good, but it is cheaper.

OTOH the silicon doesn't get as hot when soldered, I guess.

Bernhard