In a message dated 01/17/2000 6:15:44 PM Central Standard Time,
[log in to unmask] writes:
> A customer who is interested in our product has questioned the use of an
> edge card connector (90deg conn on edge of 0.060" PWB) because there is no
> solder visible in the PTH - just press pin, AKA "compliant pin" or "Action
> Pin". The connector plugs into a 0.150" backplane that also has compliant
> pin connectors. The customer wants to know if the connection of the
> compliant pin is as reliable as a non-press pin with solder fillet. I
> contacted the component manufacturer and received a 1978 tech doc that
> focused on insertion/retention forces VS PTH dias., but no specific
> references comparing press pin to solder tail. I am looking for less dated
> material, that may also include a comparison to solder tail.
>
> Does anyone out there have supporting evidence using an industry standard
> like Bellcore (TR-NWT-001217 or 000078), that speaks to the reliability of
> connectors using compliant pin technology?
>
> -Rick Mills
Hi Rick!
Here's a couple of web sites to visit, realize though, that these are pages
from the manufacturers of the connectors and may be somewhat biased. But from
my experience, provided all the design guidelines are followed from the
manufacturer of the connector being used (finished hole diameters, etc...)
that press-fit technology has many benefits. The biggest one is the ease of
installing them. Once you have the correct tooling and the board has been
designed correctly, there isn't much that can go wrong...you just press em'
in! Piece-o-cake!
Unlike soldered connectors which you have the myriad of solder defects that
you have to deal with...bridging, insufficient solder,etc...not to mention
the thermal shock that you subject the board to (if these connectors are the
only through-hole that needs wave solder). Rework ability of these coonectors
is something to consider too, if you have a individual pin that was either
bent, or fails for whatever reason, you won't have to remove the whole
connector, you can rework the individual pin with most press-fit connectors.
From my contract manufacturing experience, I've assembled many different
boards that use Press-fit technology...from large networking hardware
companies, to high speed ADSL technology assemblies, to hi-rel military
printed circuit assemblies, I have yet to see any customer switch from
press-fit technology back to soldered connectors...if there has been any
problems with it, it all has had to do with the bare PCB not meeting finished
hole sizes...too thick a HASL and the barrels failing from getting pushed out
of the fab when trying to press the connectors in. Hole sizes are VERY
critical! But that aspect shouldn't be that hard to meet provided the
critical nature of finished hole diameters are communicated to your fab
vendor due to the use of press-fit technology...here's the sites:
http://www.ept.de/usa/pressfit_technology.htm
http://www.conec.com/section7/sharedpages/pg2.php3
http://www.molex.com/product/backplan/cpin.html
http://www.positronic.com/power_4.htm
There's many more out there, but these are a few of the ones that I could
find quickly. Ernie makes press-fit connectors as does FCI/Berg, but they
didn't turn up in my initial search. One thing from recent experience, DON'T
EVER TRY AND SOLDER A PRESS-FIT CONNECTOR!
-Steve Gregory-
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