Fall Time VI

Owning Palette: Timing VIs

Requires: Jitter Analysis Toolkit

Measures the transition duration of falling transitions in a waveform. The duration of a falling transition, or fall time, is the difference in time between its start index and end index. Wire data to the waveform input to determine the polymorphic instance to use or manually select the instance.

Details  

Fall Time (DBL)

This instance operates on the waveform data type when the Y data values are double-precision, floating-point numeric values. Use the I8 instance of this VI with integer data to reduce the size of the data and the memory usage.

	waveform is the waveform to measure. t0 specifies the start time of the waveform. dt specifies the time interval in seconds between data points in the waveform. Y specifies the data values of the waveform.
	transitions contains information about the transitions in the waveform. Use the Find Transitions VI to generate this cluster. transition is an array of clusters that describe each transition in waveform. start index specifies the sample of waveform at which the transition begins. end index specifies the sample of waveform at which the transition ends. slope identifies the direction of the first transition in the waveform. -1 Falling Edge—Specifies the transition is a falling edge, or one with a negative slope. 1 Rising Edge (default)—Specifies the transition is a rising edge, or one with a positive slope. state levels specifies the high and low state values in the waveform and the corresponding amplitude. amplitude is the difference between high state level and low state level. high state level specifies the level at which a pulse or transition waveform is defined to be in its highest state. low state level specifies the level at which a pulse or transition waveform is defined to be in its lowest state ref levels specifies the high, middle, and low reference levels of a waveform. high ref level specifies the high reference level of the waveform in absolute units. mid ref level specifies the middle reference level of the waveform in absolute units. low ref level specifies the low reference level as a percentage (default) or in absolute units. The default is 10.00.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	fall time sequence is an array of the durations, in seconds, between the beginning and end of each falling transition.
	fall time timestamps returns timing information about the waveform that allows you to identify the times at which measurements in the corresponding sequence occur. t0 returns the time at which the first sample occurred in the original waveform. dt returns the time interval in seconds between the individual samples in the original waveform. indexes contains the index numbers of the waveform samples that represent the beginnings of edges. Each element of indexes corresponds to an element of the sequence array.
	error out contains error information. This output provides standard error out functionality.

Fall Time (I8)

This instance operates on the waveform data type when the Y data values are 8-bit signed integers.

	waveform is the waveform to measure. t0 specifies the start time of the waveform. dt specifies the time interval in seconds between data points in the waveform. Y specifies the data values of the waveform.
	transitions contains information about the transitions in the waveform. Use the Find Transitions VI to generate this cluster. transition is an array of clusters that describe each transition in waveform. start index specifies the sample of waveform at which the transition begins. end index specifies the sample of waveform at which the transition ends. slope identifies the direction of the first transition in the waveform. -1 Falling Edge—Specifies the transition is a falling edge, or one with a negative slope. 1 Rising Edge (default)—Specifies the transition is a rising edge, or one with a positive slope. state levels specifies the high and low state values in the waveform and the corresponding amplitude. amplitude is the difference between high state level and low state level. high state level specifies the level at which a pulse or transition waveform is defined to be in its highest state. low state level specifies the level at which a pulse or transition waveform is defined to be in its lowest state ref levels specifies the high, middle, and low reference levels of a waveform. high ref level specifies the high reference level of the waveform in absolute units. mid ref level specifies the middle reference level of the waveform in absolute units. low ref level specifies the low reference level as a percentage (default) or in absolute units. The default is 10.00.
	error in describes error conditions that occur before this node runs. This input provides standard error in functionality.
	fall time sequence is an array of the durations, in seconds, between the beginning and end of each falling transition.
	fall time timestamps returns timing information about the waveform that allows you to identify the times at which measurements in the corresponding sequence occur. t0 returns the time at which the first sample occurred in the original waveform. dt returns the time interval in seconds between the individual samples in the original waveform. indexes contains the index numbers of the waveform samples that represent the beginnings of edges. Each element of indexes corresponds to an element of the sequence array.
	error out contains error information. This output provides standard error out functionality.

Fall Time Details

A rising transition duration is known as rise time, and a falling transition duration is known as fall time, as shown in the following example: