User manual

Math and Measure
Measurement Description
Peak to Peak
(pkpk)
Difference between highest and lowest points in waveform. Unlike ampl, does not assume the
waveform has two levels. Peak to peak is calculated using the formula
maximum – minimum
.
Period
The time between every other pair of 50% crossings. Starting with first transition after left meas-
urement gate, period is measured for each transition pair, with values averaged to give final res-
ult.
Phase
Phase difference between signal analyzed and signal used as reference. Both signals are
measured from the 50% point of their rising edges.
Rise 20-80%
(rise2080)
Duration of pulse waveform's rising transition from 20% to 80% of the amplitude averaged for
all rising transitions between the measurement gates. On signals not having two major levels
(triangle or saw-tooth waves, for example), top and base can default to maximum and minimum,
giving less predictable results.
Rise Time
Duration of pulse waveform's rising transition from 10% to 90% of the amplitude averaged for
all rising transitions between the measurement gates. On signals not having two major levels
(triangle or saw-tooth waves, for example), top and base can default to maximum and minimum,
giving less predictable results.
RMS
Root Mean Square of data between the measure gates calculated using the formula:
Where: vi denotes measured sample values, and N = number of data points within the periods
found up to maximum of 100 periods.
Skew
Time of clock1 edge minus time of nearest clock2 edge. Both signals are measured from the
50% point of their rising edges.
Std Dev
(sdev)
Standard deviation of the data between the measure gates using the formula:
Where: vi denotes measured sample values, and N = number of data points within the periods
found up to maximum of 100 periods. This is equivalent to the rms for a zero-mean waveform.
Also referred to as AC RMS
Top
Higher of two most probable states (base is lower). Measures higher level in two-level signals.
Differs from max in that noise, overshoot, undershoot, and ringing do not affect measurement.
On signals not having two major levels (such as triangle or saw-tooth waves), the amplitude
parameter returns the same value as minimum.
Width
Width of cyclic signal determined by examining 50% crossings in data input. If first transition
after left cursor is a rising edge, waveform is considered to consist of positive pulses and width
the time between adjacent rising and falling edges. Conversely, if falling edge, pulses are con-
sidered negative and width the time between adjacent falling and rising edges. For both cases,
widths of all waveform pulses are averaged for the final result.
WidthN
(widn)
Time of cyclic signal determined by examining 50% crossings in data input. The widthN is
measured from falling edge to rising edge.
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