
5 DUT Board Performance Considerations DUT Board Design for Mixed-Signal Tests
132 System Reference, January 2001
Figure 55 Signal Lines
To avoid the crosstalk in your test circuit, you must
consider the following:
• For traces that carry high frequency signals (such as
clock), do not draw these traces in parallel.
• (If possible) Use a coaxial cable to protect any sensitive
signal from noise.
• Increase the distance between traces.
• Decrease the adjacent surfaces by bending the traces.
• Use a guard line between traces.
Troubleshooting Noise Problems
During test circuit development, you may encounter one
or several of the following problems:
• A correctly specified filter does not cut the signal as
required.
• A relay does not disconnect a signal completely.
• A weak signal shows exessive noise.
• A DC reference voltage has high frequency spikes.
Such problems are likely to be caused by poor isolation or
crosstalk.
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