CY3687 Cypress Semiconductor Corp, CY3687 Datasheet - Page 39

• Manufacturer Part Number: CY3687
• Description: KIT DEV MOBL-USB FX2LP18
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB HX2LP™r

Specifications of CY3687

• Main Purpose: Interface, USB 2.0 Host/Controller
• Utilized Ic / Part: CY7C68053
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Secondary Attributes: -
• Embedded: -
• Primary Attributes: -
• Lead Free Status / Rohs Status: Supplier Unconfirmed

12. PCB Layout Recommendations
The following recommendations must be followed to ensure
reliable high performance operation.
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Document # 001-06120 Rev *J
At least a four-layer impedance controlled board is required to
maintain signal quality.
Specify impedance targets (ask your board vendor what they
can achieve).
To control impedance, maintain trace widths and trace spacing
to within specifications.
Minimize stubs to minimize reflected signals.
Connections between the USB connector shell and signal
ground must be done near the USB connector.
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Bypass or flyback caps on VBus, near connector, are
recommended.
DPLUS and DMINUS trace lengths must be kept within 2 mm
of each other in length, with preferred length of 20 to 30 mm.
Maintain a solid ground plane under the DPLUS and DMINUS
traces. Do not allow the plane to be split under these traces.
It is preferable to have no vias placed on the DPLUS or
DMINUS trace routing.
Isolate the DPLUS and DMINUS traces from all other signal
traces by no less than 10 mm.
CY7C68053
Page 39 of 42
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