Teledyne LeCroy HDO 4000 Operators Manual - Manual (Page 60)

HDO4000 High Definition Oscilloscope
Parameter Description
None Disables parameter calculation
Num Points
(npoints) Number of points in the waveform between the measurement gates.
Overshoot-
Amount of overshoot following a falling edge. This is represented as percentage of amplitude. Overshoot-
is calculated using the formula (base - min.)/ampl x 100. On signals not having two major levels (triangle or
saw-tooth waves, for example), may not give predictable results.
Overshoot+
Amount of overshoot following a rising edge specified This is represented as a percentage of amplitude.
Overshoot+ is calculated using the formula (max. - top)/ampl x 100. On signals not having two major levels
(triangle or saw-tooth waves, for example), may not give predictable results.
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 measurement
gate, period is measured for each transition pair, with values averaged to give final result.
Period@level
(per@lv) The time between every other pair of at the level specified. Starting with first transition after left
measurement gate, period is measured for each transition pair, with values averaged to give final result.
Phase
Phase difference between signal analyzed and signal used as reference. Both signals are measured from
the 50% point of their rising edges.
Rise
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.
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.
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
Time@level
(time@lv)l Time from trigger (t=0) to crossing at a specified level.
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.
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