Agilent Technologies 54622A User Manual page 192

Making Measurements
Making time measurements automatically
Frequency
Frequency is defined as 1/Period. Period is defined as the time between the 50%
threshold crossings of two consecutive, like-polarity edges. A 50% crossing must
also travel through the 10% and 90% levels which eliminates runt pulses. The
X cursors show what portion of the waveform is being measured.
Period
Period is the time period of the complete waveform cycle. The time is measured
between the 50% points of two consecutive, like-polarity edges. A 50% crossing
must also travel through the 10% and 90% levels which eliminates runt pulses.
The X cursors show what portion of the waveform is being measured.
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.
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.
+ 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.
– 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.
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