Instructions
How to prevent signal degradation due to reflections (ringing)
- Keep the trace short (best solution, but often impossible).
- Terminate at the destination (end termination).
- Problem: High sink- or source current, or both. High power
consumption.
- Solution: capacitive coupling to the terminating resistor.
Time constant should be longer than the transition, but much
shorter than the flat time. Example: 200 pF x 50 Ohm = 10
ns.
- Terminate at the source ( series termination).
- Advantage: no static power consumption.
- Problem: use only for single-destination. 50% amplitude
along the trace.
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