Issue link: https://iconnect007.uberflip.com/i/1529118
30 DESIGN007 MAGAZINE I NOVEMBER 2024 ground pours do not significantly reduce crosstalk. 4. Ground pours have the disadvantage of altering the impedance of traces that run adjacent to a pour area, causing reflections. 5. If you must use copper pours to balance etching, use a 20-mil clearance from the pour to any signal trace to avoid crosstalk. 6. Crosstalk is typically picked up on long parallel trace segments. Traces should be spaced by three times the trace thickness where possible. 7. Avoid long parallel segments > 500 mils. 8. Avoid inadvertent broadside coupling on adjacent dual stripline layers. 9. Route adjacent dual striplines orthogonally to minimize coupled regions. 10. e lowest crosstalk is obtained using the narrowest traces with the highest imped- ance. 11. Use slow rise time signals or use a series terminator to slow the rise time. 12. Reduce the driver fanout/number of loads. 13. Reduce the driver strength. Mid-range is generally fine but should be checked by simulation. 14. Route on stripline (inner layers) rather than microstrip (outer layers). is also reduces EMI. 15. Ensure that you don't exceed the maxi- mum crosstalk of 150 mV. 16. e propagation delay of a serpentine trace is less than the delay through an equivalent-length straight trace because of forward crosstalk. 17. Forward crosstalk or far-end crosstalk does not exist in the stripline configura- tion. 18. Crosstalk can be coupled trace-to-trace on the same layer or can be broadside coupled by traces on adjacent layers. e coupling is three-dimensional. 19. e higher the aggressor voltage, the more crosstalk will be induced. It is therefore best to segregate groups of nets according to their signal amplitude. 20. e easiest way to reduce crosstalk from Figure 5: Parallel segment crosstalk.