tin vs gold plated connectors

[PDRUNEN]

Hi Group,

When would I select a gold plated connector over the standard tin plated?

Tnx

Paul

 

[Mike Harrison]

Hi Group,

When would I select a gold plated connector over the standard tin plated?

Tnx

Paul

If you need durability (many insert/remove cycles), consistent contact resistance over time and
insert cycles.
If you need low insertion force (e.g. on large pin counts)
I think it also has better themal emf performance, which is desirable for very low level signals.

There are probably other differences but I thing these are the main ones.

 

[Joseph Legris]

In my experience, gold plating is very bad for frequently used contacts.
It scratches through and then corrodes very rapidly through electrolysis.

Lots of consumer battery packs had gold plated terminals in the 80s and
90s. They were a hassle. My one attempt to use a gold connector on a
bicycle light was a disaster too. In all cases the gold worked great
for about a week then needed daily cleaning with a tissue.

The following articles seem to support your conclusions:

http://www.pvdijk.com/images/21thiceccriticalaspects.pdf

http://www.amp.com/products/technology/2jot_7.pdf

 

[cpemma]

Hi Group,

When would I select a gold plated connector over the standard tin
plated?

Tnx

Paul

 

[cpemma]

Hi Group,

When would I select a gold plated connector over the standard tin
plated?

It's sometimes advisable to have both sides of the connector the same metal,
to avoid galvanic corrosion/emf effects.

SIMM boards were an example, if the motherboard had tinned sockets go for a
tinned edge connector & vv.

 

[Ken Finney]

In my experience, gold plating is very bad for frequently used contacts.
It scratches through and then corrodes very rapidly through electrolysis.

Lots of consumer battery packs had gold plated terminals in the 80s and
90s. They were a hassle. My one attempt to use a gold connector on a
bicycle light was a disaster too. In all cases the gold worked great
for about a week then needed daily cleaning with a tissue.

The "flash" gold plating used on consumer products is something less
than 5 microinches, and it basically a marketing gimic. Legitimate
gold plating is something like 50 microinches thick, and is an
entirely different beast.

 

[Jim Yanik]

Then the plating's not thick enough. Unforgiveable in this age when
gold's not worth a *shit* and hasn't been for 15 years at least!

Yes,there's good gold plating,and there's BAD gold plating.
But tin grows whiskers that can short out the connector.

 

[Ken Smith]

Yes,there's good gold plating,and there's BAD gold plating.
But tin grows whiskers that can short out the connector.

There is also good connector design and bad connector design. The best
plating won't make up for a connector that either (a) chews the gold off,
or (b) doesn't have enough sping in the female contact.

 

[Jim Yanik]

[email protected] (Ken Smith) wrote in

There is also good connector design and bad connector design. The
best plating won't make up for a connector that either (a) chews the
gold off, or (b) doesn't have enough sping in the female contact.

Gold can be plated in varying hardness levels,too.And tin is just as
susceptible to getting "chewed off",it's not that hard of a metal.Gold is
the best.

 

[Ken Smith]

Gold can be plated in varying hardness levels,too.

"Hard gold" has nickle in it. This is a bad thing in my industry. I can
detect hard gold platings easily. If there is a nickle layer under the
gold its very easy to spot.

And tin is just as
susceptible to getting "chewed off",it's not that hard of a metal.Gold is
the best.

I didn't mean to imply that tin worked well on badly designed connectors.

 

[Sven Hegewisch]

[email protected] (Ken Smith) wrote in


ISTR you have to have the layer of nickel to get proper adhesion of the
gold.I'm no plating expert,just recalling(perhaps imperfectly) what TEK
engineering notes said about gold plating.
Metallurgists will know the right way.

The nickel layer is a diffusion barrier for the gold which would
otherwise
diffuse rather fast into copper below.

Sven Hegewisch

 

[Ken Smith]

The nickel layer is a diffusion barrier for the gold which would
otherwise
diffuse rather fast into copper below.

It also serves to make a hard, very flat and smooth surface. When gold
cost a lot, it was worth while for the makers of pins to put down nickel
and then put about 2 atoms of gold on top of it instead of the thicker
gold layer they did before that time.