User`s guide

Elan Digital Systems Ltd. 18 AD125 USER’S GUIDE
3.4.2 TRIGGER MODES
There are various configurations of trigger on the AD125, they are
summarised below:
+ET
TREDGE=1 LVL=0
-ET
TREDGE=0 LVL=0
>
TREDGE=1 LVL=1
<
TREDGE=0 LVL=1
TRIGGER WHEN
I/P TRANSITIONS
FROM BELOW
Vtrig TO ABOVE
Vtrig
TRIGGER WHEN
I/P TRANSITIONS
FROM ABOVE
Vtrig TO BELOW
Vtrig
TRIGGER
WHENEVER I/P IS
ABOVE Vtrig
TRIGGER
WHENEVER I/P IS
BELOW Vtrig
The modes are programmed via SETUP REG 2.
The AD125 can also be trigged externally via the nTRIGGER edge
connector signal. The signal is pulled up by 10K to Vcc inside the
card. Pulse the line low for a minimum of one sample period to
ensure the triggering is effective. This may mean external pulse
stretching is required for some applications.