Tektronix DPO5034B, Руководство пользователя

Страница: 140 / 222

Analyzing waveforms
Automated measurement selections
The following tables list each automated measurement by category: amplitude, time, histogram, communication, or more.
(See page 116,
Taking automatic measurements .)
Amplitude measurements
Measurement Description
Amplitude The high value less the low value measured over the entire waveform or gated region.
High This value is used as 100% whenever high reference, mid reference, or low reference values are
needed, such as in fall time or rise time measurements. It is calculated using either the min/max or
histogram method. The min/max method uses the maximum value found. The histogram method
uses the most common value found above the midpoint. This value is measured over the entire
waveform or gated region.
Low This value is used as 0% whenever high reference, mid reference, or low reference values are
needed, such as in fall time or rise time measurements. It is calculated using either the min/max or
histogram method. The min/max method uses the minimum value found. The histogram method
uses the most common value found below the midpoint. This value is measured over the entire
waveform or gated region.
RMS The true Root Mean Square voltage over the entire waveform or gated region.
AC RMS The true Root Mean Square voltage over the measurement region.
Max The most positive peak voltage. Max is measured over the entire waveform or gated region.
Min The most negative peak voltage. Min is measured over the entire waveform or gated region.
Pk-Pk The absolute difference between the maximum and minimum amplitude in the entire waveform
or gated region.
Cycle RMS The true Root Mean Square voltage over the fi rst cycle in the waveform or the fi rst cycle in the
gated region.
+Overshoot This is measured over the entire waveform or gated region and is expressed as:
Positive Overshoot = ((Maximum - High) / Amplitude) x 100%.
-Overshoot This is measured over the entire waveform or gated region and is expressed as:
Negative Overshoot = ((Low - Minimum) / Amplitude) x 100%.
Mean The arithmetic mean over the entire waveform or gated region.
Cycle Mean The arithmetic mean over the fi rst cycle in the waveform or the fi rst cycle in the gated region.
Time measurements
Measurement Description
Rise Time The time required for the leading edge of the fi rst pulse in the waveform or gated region to rise from
the low reference value (default = 10%) to the high reference value (default = 90%) of the fi nal value.
Fall Time The time required for the falling edge of the fi rst pulse in the waveform or gated region to fall from
the high reference value (default = 90%) to the low reference value (default = 10%) of the fi nal value.
Pos Width
The distance (time) between the mid reference (default 50%) amplitude points of a positive pulse.
The measurement is made on the
fi rst pulse in the waveform or gated region.
Neg Width The distance (time) between the mid reference (default 50%) amplitude points of a negative pulse.
The measurement is made on the
fi rst pulse in the waveform or gated region.
+ Duty Cyc The ratio of the positive pulse width to the signal period expressed as a percentage. The duty cycle
is measured on the
fi rst cycle in the waveform or gated region.
118 MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series User Manual