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New iStar ICCD
Operation
Limitations
WhEN USING EXTERNAL TRIGGER WITH IOC AND GATE STEP THE SOFTWARE HAS TO COMMUNICATE TO THE
DDG IN BETWEEn scans in order to increment the gate delay. The time needed is :
•
7.5 ms
when incrementing the gate delay
•
11.5 ms
when incrementing the gate delay, output A delay, output B delay, output C delay
(if track gate step is enabled)
This time is in most cases less than the time it takes to clean out the image area before each exposure.
Therefore
precautions only need to be taken when the time to clean out the image area is less than 7.5 ms (or 11.5 ms if
other channels are tracking the gate step)
. Since this clean cycle depends on the sensor and vertical shift speed
combination the table below shows the recommended settings. Unless stated otherwise the maximum trigger rate is to
500 kHz (5 khz for intelligate).
a) When incrementing the gate delay only:
When using trigger rates
less than 133 Hz,
the recommended setup is:
Vertical Shift Speed (µsecs)
DH334T (47-10 sensor)
6.5
DH320T (30-11 sensor)
11.3
DH340T (42-10 sensor)
12.9
DH312T (77-00 sensor)
6.5
When using trigger rates
greater than 133 Hz,
the recommended setup is:
Vertical Shift Speed (µsecs)
Clean Cycle (msecs)
for information only
DH334T (47-10 sensor)
6.5
13.5
DH320T (30-11 sensor)
22.5
9.3
DH340T (42-10 sensor)
12.9
10
DH312T (77-00 sensor)
12.9
8.8
