LeCroy DDA 7 Zi series, Operator'S Manual

Page: 239 / 544

Operator's Manual
WP700Zi-OM-E-RevA
238
Qualified First
Not available on all scopes, Qualified First trigger is intended to be used exclusively in Sequence Mode
to speed up the trigger rate. With Qualified First trigger, a single valid trigger is sufficient to acquire a full
sequence. Other than in Sequence Mode, Qualified First is identical to the Qualified triggers.
In data storage applications, the index pulse can be defined as the qualifier signal and the servo gate signal as
the trigger source.
State
The State trigger is a level-qualified trigger which requires that the qualifying signal remain above or below
a specified voltage level for a trigger to occur. For Sate trigger, you specify the time or number of events after the
signal has gone above or below the voltage level when you want the trigger to occur.
Dropout
Used primarily in single-shot applications, and usually with a pre-trigger delay, Dropout trigger can detect
lost signals. The trigger is generated at the end of the timeout period following the last trigger source transition.
Logic
Logic trigger enables triggering on a logical combination (pattern) of five inputs: CH1, CH2, CH3, CH4,
EXT. You have a choice of four Boolean operators (AND, NAND, OR, NOR), and you can stipulate the high or low
voltage logic level for each input independently.
TV
Not available on all instruments, TV triggers provide stable triggering on standard or custom composite
video signals. Use them on PAL, SECAM, or NTSC systems.
Slew Rate
SlewRate trigger activates a trigger when the rising or falling edge of a pulse crosses two threshold levels:
an upper level and a lower level. The pulse edge must cross the thresholds faster or slower than a selected
period of time. You can select both thresholds within a range of 2 ns to 20 s. Slew rate trigger is not available on
all instruments.
Runt
The Runt trigger occurs when a pulse crosses a first threshold line, but fails to cross a second threshold
line before recrossing the first. You can select both voltage thresholds within a time range of 100 ps to 20 s. Other
defining conditions for this trigger are the edge (triggers on the slope opposite to that selected) and runt width.
Serial Trigger and Decode
Serial trigger allows a serial trigger condition to be set from within the oscilloscope, using an easy-to-
understand interface.