LeCroy LSA1000, Operator'S Manual

Page: 91 / 115

C – 7
Parameter Measurement
Parameter — Description Definition Notes
dur Duration of acquisition: For single sweep
waveforms,
dur is 0; for sequence
waveforms: time from first to last
segment’s trigger; for single segments of
sequence waveforms: time from previous
segment’s to current segment’s trigger;
for waveforms produced by a history
function: time from first to last
accumulated waveform’s trigger.
Time from first
acquisition
— for
average,
histogram or
sequence
waveforms
duty Duty cycle: Width as percentage of
period. width/period
(See Fig. C
–2)
f80
–20%
Fall 80
–20 %: Duration of pulse
waveform's falling transition from 80% to
20%, averaged for all falling transitions
between the cursors.
Average duration
of falling
80
–20 %
transition
On signals
NOT
having two major
levels (triangle or saw-tooth
waves, for example), top and
base can default to maximum
and minimum, giving, however,
less predictable results.
f@level Fall at level: Duration of pulse waveform's
falling edges between transition levels. Duration of
falling edge
between
transition levels
On signals
NOT
having two major
levels (triangle or saw-tooth
waves, for example), top and
base can default to maximum
and minimum, giving, however,
less predictable results.
fall Fall time: Measures time between two
specified values on falling edges of a
waveform. Fall times for each edge are
averaged to produce final result. Time at lower
threshold -
Time at upper
threshold
averaged over
each falling edge
(See Fig. C
–1)
On signals
NOT
having two
major levels (triangle or saw-
tooth waves, for example), top
and base can default to
maximum
and minimum,
giving, however, less
predictable results.
Arguments
Threshold Remote Lower
Limit
Upper
Limit
Default
Lower low 1 % 45 % 10 %
Upper high 55 % 99 % 90 %
Threshold arguments specify two vertical values
on each edge used to compute fall time.
Formulas for upper and lower values:
lower value lower threshold
=  +
amp
base
100
upper value upper threshold
=  +
amp
base
100