USB-PD TDMP Instruction Manual
Graphing Measurements
The Measure/Graph package include simplified methods for plotting measurement values as:
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Histogram - a bar chart of the number of data points that fall into statistically significant intervals or bins. Bar
height relates to the frequency at which data points fall into each interval/bin. Histogram is helpful to
understand the modality of a parameter and to debug excessive variation.
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Trend - a plot of the evolution of a parameter over time. The graph's vertical axis is the value of the parameter;
its horizontal axis is the order in which the values were acquired. Trending data can be accumulated over many
acquisitions. It is analogous to a chart recorder.
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Track - a time-correlated accumulation of values for a single acquisition. Tracks are time synchronous and
clear with each new acquisition. Track can be used to plot data values and compare them to a corresponding
analog signal, or to observe changes in timing. A parameter tracked over a long acquisition could provide
information about the modulation of the parameter.
To graph a measurement, just select the plot type from the Measure/Graph dialog when setting up the
measurement. All plots are Math functions that open along side the deocoding in a separate grid.
Measure/Graph Setup Dialog
Use the Measure/Graph Setup dialog to select the parameter to apply to the decoded waveform while
simultaneously graphing the results.
1. Select the Measurement to apply and the Destination parameter (P
n
) to which to assign it.
2. The active decoder is preselected in Source 1, indicating the measurement will be applied to the decoder
results; change it if necessary. If the measurement requires it, also select an appropriate Source 2 (such as an
analog waveform for comparison).
3. Optionally:
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Touch
to select a plot type. Also select a Destination function (F
n
) for the plot.
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Touch Apply & Configure to set a filter, gate or other qualifiers on the measurement.
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Содержание USB-PD TDMP
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