Tektronix TDS 684A, TDS 744A, TDS 784A - page 126

Triggering on Waveforms
TDS 684A, TDS 744A, & TDS 784A User Manual 3–71
subsection describes how to use each of the four classes of pulse triggers: glitch,
runt, width, and slew rate triggering.
A glitch trigger occurs when the trigger source detects a pulse narrower (or
wider) in width than some specified time. It can trigger on glitches of either
polarity. Or you can set the glitch trigger to reject glitches of either polarity.
A runt trigger occurs when the trigger source detects a short pulse that crosses
one threshold but fails to cross a second threshold before recrossing the first. You
can set the oscilloscope to detect positive or negative runt pulses.
A width trigger occurs when the trigger source detects a pulse that is inside or,
optionally, outside some specified time range (defined by the upper limit and
lower limit). The oscilloscope can trigger on positive or negative width pulses.
A slew rate trigger occurs when the trigger source detects a pulse edge that
traverses (slews) between two amplitude levels at a rate faster than or slower
than you specify. The oscilloscope can trigger on positive or negative slew rates.
You can also think of slew rate triggering as triggering based on the slope
(change in voltage/change in time) of a pulse edge.
Figure 3–43 shows the pulse trigger readout. Table 3–8, on page 3–71, describes
the choices for pulse triggers.
Trigger Class = Runt
Figure 3–43: Pulse Trigger Readouts
Table 3–8: Pulse Trigger Definitions
Name Definition
Glitch positive Triggering occurs if the oscilloscope detects positive spike
widths less than the specified glitch time.
Glitch negative Triggering occurs if the oscilloscope detects negative spike
widths less than the specified glitch time.
Glitch either Triggering occurs if the oscilloscope detects positive or
negative widths less than the specified glitch time.