If the input signal trace of a CMOS logic IC is in the vicinity of an output signal trace of another IC, crosstalk noise might be generated. Check if another trace is in the vicinity of the input signal trace or runs adjacently in parallel.
Generally, the following countermeasures can be considered:
For a description of crosstalk, please refer to “Precaution when Designing Circuits: Logic ICs”.
CMOS Logic ICs Usage Considerations (PDF:1.61MB)
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