HP 16534A User Reference page 103

Positive Pulse Width (+Width)
Pulse width is measured at the 50% voltage level.
If the first edge on the display is rising, then
+Width = t
falling edge 1
If the first edge on the display is falling, then
+Width = t
falling edge 2
Negative Pulse Width (−Width)
Negative pulse width is the width of the first negative pulse on screen using
the 50% levels.
If the first edge on the display is rising, then
−Width = t
rising edge 2
If the first edge on the display is falling, then
−Width = t
rising edge 1
Rise time
The rise time of the first displayed rising edge is measured. To obtain the
best possible measurement accuracy, set the sweep speed as fast as possible
while leaving the full leading edge of the waveform on the display. The rise
time is determined by measuring time at the 10% and 90% voltage points on
the rising edge:
−t
Rise time = t
90% 10%
− t
.
rising edg e 1
− t
.
rising edg e 1
− t
.
edg e 1
falling
− t
.
edg e 1
falling
.
The Auto-Measure Menu
Measurement Algorithms
8-9