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Automatic measurement of the time parameters
The oscilloscope provides automatic measurements of time parameters including Frequency, Period, Rise
Time, Fall Time, +Width, -Width, Delay A→B , Delay A→B and Duty Cycle.
The following picture shows a pulse with some timing points:
Rise Time: The time it takes for the leading edge of the first pulse in the curve to rise from 10% to 90% of its
amplitude.
Fall Time: The time it takes for the leading edge of the first pulse in the curve to fall from 90% to 10% of its
amplitude.
+D Width: The width of the first positive pulse at the 50% amplitude point.
-D Width: The width of the first negative pulse at the 50% amplitude point.
+ Duty: + duty cycle, defined as +width/period.
- Duty: - duty cycle, defined as -width/period.
Delay A→B : The delay between the two channels on the rising edge.
Delay A→B : The delay between the two channels at the falling edge.
Duty cycle: Defined as (Width of positive pulse)/(Total period)
Phase: Compares the rising edge of CH1 and CH2, calculates the phase difference of the two channels.
Phase difference= [(delay between channels of the rising edge) x PI]/period
Other measurement functions
+PulseCount : Displays the number of positive pulses that rise above the centre reference transition.
-PulseCount : Displays the number of negative pulses that are under the centre reference transition.
+PulseCount : Displays the number of positive passes from the low reference value to the high
reference value.
-PulseCount : Displays the number of negative passes from the high reference value to the low
reference value.
Area : Calculates the total area of the waveform as volt-seconds. The area above the zero reference
(the vertical offset) is positive and the area below the zero reference is negative. The measurement area is
the algebraic sum of the waveform displayed on the screen.
Cycle Area : Calculates the range of the first period of the waveform as a volt-second. The area
above the zero reference (the vertical offset) is positive and the area below the zero reference is negative.
The measurement area is the algebraic sum of the first period of the waveform.
Note: If less than a complete period is shown on the display, the measuring range is 0.
Rise Time
Fall Time
+Width -Width