What are the possible causes of noise in the voltage waveform input to the CMOS logic IC
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:
- Adding a guard trace such as a GND trace between signal and adjacent traces.
- Reducing the length of the trace that runs in parallel with a signal trace.
For a description of crosstalk, please refer to “Precaution when Designing Circuits: Logic ICs”.
CMOS Logic ICs Usage Considerations (PDF:1.61MB)
Related Links
The following documents also contain related information.
Product Lists
FAQs
- Is a decoupling capacitor required for the supply of a general purpose logic IC?
- Is it possible to leave the unused inputs of the general purpose logic ICs open?
- Are there any problems with the input pins of CMOS logic ICs and the bus pins (input/output pins) of bidirectional bus buffers in a floating state?
Application Notes
A new window will open