The A/D trigger logic can initiate an A/D conversion upon an
external trigger. Valid external trigger signals must be TTL compatible
and meet minimum pulse width requirements. The requirements are shown
below:
t
re
t
du
External trigger
Symbol Name Minimum
Maximum
T
du
Duration time
40ns
∞
T
re
Recover time
100ns
∞
Note: The OME-PCI-1002 is designed only for time sensitive triggers
(trigger is dependent only on the time of the falling edge of
signal). For a level sensitive external trigger (trigger is dependent
on the level of the input signal), the user can build the following
external circuit the OME-PCI-1002:
DAC
OME-PCI-
1002 D/O
Input Signal
Comparator
TTL buffer
External
Trigger
37
Summary of Contents for OME-PCI-1002
Page 21: ...Figure 2 4 Figure 2 5 21 ...
