Agilent Technologies 41A Making time measurements automatically Fall Time, Rise Time, + Width

Making Measurements

Making time measurements automatically

Fall Time

The fall time of a signal is the time difference between the crossing of the upper threshold and the crossing of the lower threshold for a negative-going edge. The X cursor shows the edge being measured. For maximum measurement accuracy, set the sweep speed as fast as possible while leaving the complete falling edge of the waveform on the display. The Y cursors show the 10% and 90% points.

Rise Time

The rise time of a signal is the time difference between the crossing of the lower threshold and the crossing of the upper threshold for a positive-going edge. The X cursor shows the edge being measured. For maximum measurement accuracy, set the sweep speed as fast as possible while leaving the complete rising edge of the waveform on the display. The Y cursors show the 10% and 90% points.

+Width

+Width is the time from the 50% threshold of the rising edge to the 50% threshold of the next falling edge. The X cursors show the pulse being measured. The Y cursor shows the 50% point.

–Width

–Width is the time from the 50% threshold of the falling edge to the 50% threshold of the next rising edge. The X cursors show the pulse being measured. The Y cursor shows the 50% point.

X at Max

X at Max is the X axis value (usually time) at the first displayed occurrence of the waveform Maximum, starting from the left-side of the display. For periodic signals, the position of the maximum may vary throughout the waveform. The X cursor shows where the current X at Max value is being measured.

To measure the peak of an FFT:

aSelect FFT as the math function in the Math menu. b Choose Math as the source in the Quick Meas menu. c Choose Maximum and X at Max measurements.

Maximum units are in dB and X at Max units are in Hertz for FFT.

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