HP 54522A - Page 260

Trigger Modes
Specifications and Characteristics
Operating Characteristics
Edge Trigger
You can select a positive or negative edge for trigger on any channel, the
external trigger input (HP 54520A/54540A), or the auxiliary input. For the
channel and external trigger sources, you can set coupling to dc, ac (10 Hz) ,
or Ifre] (ow frequency reject, 50 kHz). Trigger coupling is independent of
the vertical signal coupling and noise reject. This coupling only applies in the
edge mode. In all other trigger modes, the channel and external trigger
coupling is set to dc. You can also select line trigger in the edge trigger
menu. Trigger coupling is automatically set to dc for all sources in all trigger
modes, except in the edge trigger mode.
Pattern Trigger
You can specify a pattern using any front panel channel or external trigger
input. Each input can be specified as a high, low, or don’t care with respect to
the level setting in the edge trigger menu. The trigger can be selected to
occur on the last edge to enter the specified pattern or the first edge to exit
the specified pattern. This pattern must be present for at least 1.75 ns before
the trigger will respond.
Time Qualified Pattern Trigger A trigger occurs on the first edge to
exit a pattern only if it meets the specified time criteria. The available
time qualified modes are (user-specified time is in brackets):
pattern present < [time]
® pattern present > [time]
@ range: pattern present > [timel] and < [time2]
The time settings are adjustable from 20 ns to 160 ms (+3% +2 ns). The time
filter recovery time is $12 ns. In the "pattern present < [time]}" mode, the
pattern must be present for at least 1.75 ns before the trigger will respond.
Glitch Pattern Trigger Pattern triggering can be used to glitch trigger
in conjunction with a pattern. Using any front panel channel or external
trigger input. Use “pattern present < [time]" with [time] selected such
that it is just less than the nominal pulse width of the signal you are
analyzing. The minimum glitch width is 1 ns.
You can use the Glitch Trigger mode for glitch triggering on single sources
with glitch widths from 1 ns to 160 ms.
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