Timing and Transition Measurements Express VI

Owning Palette: Signal Analysis Express VIs

Requires: Full Development System

Performs timing and transition measurements, such as frequency, period, or duty cycle, on a signal, usually a pulse.

Dialog Box Options
Block Diagram Inputs
Block Diagram Outputs
 Add to the block diagram  Find on the palette

Dialog Box Options

ParameterDescription
Timing and Transition MeasurementsContains the following options:
  • Frequency—Calculates the frequency of Signals in Hertz.
  • Period—Calculates the time in seconds between adjacent middle reference level crossings in the same direction. The reciprocal of this value is the signal frequency.
  • Pulse duration—Calculates the time difference in seconds between the first two middle reference level crossings. Pulse duration also is known as pulse width.
  • Duty cycle—Calculates the Pulse duration as a fraction of the Period.

  • Preshoot (%)—Calculates the height of the local minimum that precedes a rising transition or the local maximum that precedes a falling transition as a percentage of the histogram-based amplitude of the signal.
  • Overshoot (%)—Calculates the height of the local maximum that follows a rising transition or the local minimum that follows a falling transition as a percentage of the histogram-based amplitude of the signal.
  • Slew rate—Calculates the ratio between (90% amplitude – 10% amplitude) and the rise time.
ResultsDisplays the measurement you configured this Express VI to perform and the calculated value of that measurement. You can click any measurement listed in the Measurement column, and the corresponding value or plot appears in the Result Preview graph.
Input SignalDisplays the input signal. If you wire data to the Express VI and run it, Input Signal displays real data. If you close and reopen the Express VI, Input Signal displays sample data until you run the Express VI again.
Result PreviewDisplays a preview of the measurement. The Result Preview plot indicates the value of the selected measurement with a dotted line. If you wire data to the Express VI and run the VI, Result Preview displays real data. If you close and reopen the Express VI, Result Preview displays sample data until you run the VI again. If the cutoff frequency values are invalid, Result Preview does not display valid data.

Block Diagram Inputs

ParameterDescription
SignalsContains the input signal or signals.
error inDescribes error conditions that occur before this node runs.

Block Diagram Outputs

ParameterDescription
Slew RateReturns the ratio between (90% amplitude – 10% amplitude) and the rise time.
PreshootReturns the height of the local minimum that precedes a rising transition or the local maximum that precedes a falling transition as a percentage of the histogram-based amplitude of the signal.
DurationReturns the time difference in seconds between the first two middle reference level crossings.
PeriodReturns the time in seconds between adjacent middle reference level crossings in the same direction. The reciprocal of this value is the signal frequency.
FrequencyReturns the frequency of Signals in Hertz.
Duty CycleCalculates the Pulse duration as a fraction of the Period.

OvershootReturns the height of the local maximum that follows a rising transition or the local minimum that follows a falling transition as a percentage of the histogram-based amplitude of the signal.
error outContains error information. This output provides standard error out functionality.

This Express VI operates similarly to the following VIs and functions:

Pulse Measurements
Transition Measurements

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