Q: How to route high-speed signals through connectors and cables without signal degradation?
Answer
At connectors maintain controlled impedance to within +-10%. Pinout: place ground pins adjacent to high-speed signal pairs. Use impedance-matched connectors. For FFC/FPC cables >5 cm at USB 3.0 speeds use 85 Ohm impedance cable and specify it to the cable vendor. Avoid stubs at connector junctions – use blind/buried vias or back-drill. For board-to-board connectors select connectors with dedicated ground pins between signal pairs. Keep cable lengths as short as possible. For EMI use shielded cable for USB 3.0+ and terminate shields with 360-degree grip to connector shell with low impedance (ferrite sleeve). The return current must have a continuous path through the connector.
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