Fall time of negativegoing bilevel waveform transitions
F = falltime(X)
F = falltime(X,FS)
F = falltime(X,T)
[F,LT,UT]
= falltime(...)
[F,LT,UT,LL,UL]
= falltime(...)
[...] = falltime(...,Name,Value)
falltime(...)
returns a vector, F
= falltime(X
)F
, containing the time each
transition of the bilevel waveform, X
, takes
to cross from the 90% to 10% reference levels. See Percent Reference Levels. To determine
the transitions, falltime
estimates the state
levels of the input waveform by a histogram method. falltime
identifies
all regions, which cross the lowerstate boundary of the high state
and the upperstate boundary of the low state. The lowstate and highstate
boundaries are expressed as the state level plus or minus a multiple
of the difference between the state levels. See StateLevel Tolerances. Because falltime
uses
interpolation, F
may contain values that do not
correspond to sampling instants of the bilevel waveform, X
.
specifies
the sampling frequency in hertz. The sampling frequency determines
the sample instants corresponding to the elements in F
= falltime(X
,FS
)X
.
The first sample instant in X
corresponds to t=0.
Because falltime
uses interpolation, F
may
contain values that do not correspond to sampling instants of the
bilevel waveform, X
.
specifies
the sample instants, F
= falltime(X
,T
)T
, as a vector with the
same number of elements as X
.
[
returns vectors, F
,LT
,UT
]
= falltime(...)LT
and UT
,
whose elements correspond to the time instants where X
crosses
the lower and upper percent reference levels.
[
returns the levels, F
,LT
,UT
,LL
,UL
]
= falltime(...)LL
and UL
,
corresponding to the lower and upperpercent reference levels.
[...] = falltime(...,
returns
the fall times with additional options specified by one or more Name,Value
)Name,Value
pair
arguments.
falltime(...)
plots the signal and darkens
the regions of each transition where fall time is computed. The plot
marks the lower and upper crossings and the associated reference levels.
The state levels and the associated lower and upperstate boundaries
are also displayed.

Bilevel waveform. 

Sample rate in hertz. 

Vector of sample instants. The length of 

Reference levels as a percentage of the waveform amplitude.
The lowstate level is defined to be 0 percent. The highstate level
is defined to be 100 percent. See Percent Reference Levels. Default: 

Low and highstate levels. Specifies the levels to use for the low and highstate levels as a 2element realvalued row vector whose first and second elements correspond to the low and highstate levels. 

Tolerance levels (lower and upperstate boundaries) expressed as a percentage. See StateLevel Tolerances. Default: 

Fall times. 

Instants when negativegoing transition crosses the lowerreference
level. By default, the lowerreference level is the 10% reference
level. You can change the default reference levels by specifying the 

Instants when negativegoing transition crosses the upperreference
level. By default, the upper reference level is the 90% reference
level. You can change the default reference levels by specifying the 

Lowerreference level in waveform amplitude units. 

Upperreference level in waveform amplitude units. 
[1] IEEE^{®} Standard on Transitions, Pulses, and Related Waveforms, IEEE Standard 181, 2003, pp. 15–17.