User manual

Digital Interface Tester
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AM700 Audio Measurement Set User Manual
Eye Diagram Display
Use the eye diagram display seen in Figure 4-63 is to view binary-coded digital
signals to see the voltage levels used to represent the two logic states and the
transitions between them. Proper distance between the logic levels, as well as proper
position of the transitions, is important for error-free data transmission.
Figure 4-63: Digital Interface Tester eye diagram
Using an oscilloscope, eye patterns are typically formed by triggering at some
fraction of the serial clock frequency while observing amplitude changes in the
serial bit stream. Sometimes the serial signal is holding at a low or high logic level,
and sometimes it is switching between levels. These combinations end up producing
an overlaid display showing both logic levels and all transitions between the levels.
In between the transitions, the separation or distance of the two logic levels must be