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What are the major costs to build
a connector? Which of these are
the bigger costs? In other words,
what is the most expensive part
of a connector? Excluding cable
assemblies, the major costs in most
board level connectors are the plastic
body, the pins, plating on the pins,
the labor to assemble it, and the
packaging. Often, the bigger ticket
items are the pins and the plating.
For example, on a micro pitch, high
density interconnect product, the
pin and plating may account for
up to 30% of the total cost of the
connector. But on a basic 2.54 mm
centerline terminal strip (“header’),
it can account for well over 50% of
the total cost of the connector. (See
Figure 1)
The relative size of the plastic body
the cost principles apply to many
other interconnect brands as well.
Common Base Metals
The three most common base metals
for most board-to-board connectors
are brass, beryllium copper, and
phosphor bronze.
Brass
Brass is the least expensive of the
three metals and has excellent
electrical properties. Having said
that, brass has low yield strength.
Because of this, Samtec recommends
not using brass in contacts. The
concern is the brass beams on the
socket will take a permanent set.
Meaning, after cycling, the socket
beams will spring back to their
original position and the terminal
Selecting The Best Pin Material and Plating Option
For My Connector
Danny Boesing, Samtec, Inc.
on a miniature, mold-to-position
micro connector is almost always
larger than the body on a basic cut-
to-position strip-line connector. In
other words, there’s more plastic
in most micro-pitch interconnects,
compared to bigger pitch strip
headers. And, of course, the pins
are going to cost more if you’re
using gold plating.
Therefore, selecting the right pin and
plating significantly impacts the cost
of the connector system. This article
is a quick overview of three different
base metals commonly used in
terminal pins and sockets, and it
discusses different plating options
available, what most customers use,
and why. Disclaimer: The majority
of examples in this article relate to
Samtec interconnects, but I assume
Connectors & Cables
Special Edition
42 l New-Tech Magazine Europe