PCM-C418/Best Practices
v1.0
www.winsystems.com
Page 49
Power Harness
Minimize the length of the power harness. This reduces the amount of voltage drop
between the power supply and the PCM-C418.
Gauge Wire
Use the largest gauge wire that you can. Most connector manufacturers have a
maximum gauge wire they recommend for their pins.
Contact Points
WinSystems’ boards mostly use connectors with gold finish contacts. Gold finish
contacts are used exclusively on high-speed connections. Power and lower speed
peripheral connectors may use a tin finish as an alternative contact surface. It is critical
that the contact material in the mating connectors is matched properly (gold to gold and
tin to tin). Contact areas made with dissimilar metals can cause oxidation/corrosion,
resulting in unreliable connections.
Power Down
Make sure that the system is
completely off/ powered
down before making or breaking
any connections.
I/O Connections OFF
—I/O connections should also be off before connecting them to
the PCM-C418 or any I/O cards. Connecting hot signals can cause damage whether the
PCM-C418 is powered or not.
Mounting and Protecting the PCM-C418
The PCM-C418 must be mounted properly to avoid damage.
Do not bend or flex the PCM-C418
—Bending or flexing can cause irreparable damage.
Embedded computer modules are especially sensitive to flexing or bending around
ball-grid-array (BGA) devices. BGA devices are extremely rigid by design and flexing or
bending the embedded computer module can cause the BGA to tear away from the
printed circuit board.
Mounting holes
—The mounting holes are plated on the top, bottom, and through the
barrel of the hole, and are connected to the PCM-C418’s ground plane. Traces are often
routed in the inner layers right below, above or around the mounting holes.
•
Never use a drill or any other tool in an attempt to make the holes larger.
Power Supply OFF
—The power supply should always be off before it is connected to
the PCM-C418.
