Multitech MultiConnect MTPCIE-BW, Руководство разработчика

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DESIGN CONSIDERATIONS
18 MultiConnect
®
PCIe MTPCIE-H5/MTPCIE-BW Developer Guide
MultiTech uses and recommends that others use anti-static boxes that create a faraday cage (packaging designed
to exclude electromagnetic fields). MultiTech recommends that you use our packaging when returning a product
and when you ship your products to your customers.
USB Design
MultiTech recommends that you review Intel's High Speed USB Platform Design Guidelines for information about
USB signal routing, impedance, and layer stacking. Also:
Shield USB cables with twisted pairs (especially those containing D+/D-).
Use a single 5V power supply for USB devices. See Power Draw for current (ampere) requirements.
Route D+/D- together in parallel with the trace spacing needed to achieve 90 ohms differential impedance
for the USB pair and to maintain a 20 mil space from the USB pair and all other signals.
If power is provided externally, use a common ground between the carrier board and the device.