HP 54645A, Руководство пользователя и сервисное руководство

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Peak Detect versus Normal on HP 54645D Digital Channels
In a digital system design, a glitch is an unintentional or unexpected signal
transition which may or may not pass through the logic threshold. The
HP 54645D supports capturing glitches on digital channels during data
acquisition. However, because the scope cannot determine whether the
transition was valid, it defines the concept of a glitch differently. The scope
considers a glitch to be any set of two or more edges that pass through the
logic threshold and fall between logic samples.
Digital channels are not affected by the peak detect display mode. Digital
channels will always display glitches—multiple logic transitions between logic
samples—as shown in the following figure.
HP 54645D Shows Glitches
Note that the glitches are indicated by the filled-in boxes of the waveform.
You can often get more timing resolution on these channels by re-acquiring
the data at a faster sweep speed.
Figure 4-6
MegaZoom Concepts
Display Modes
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