USER
M
ANUAL
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31
2315NDT v2 CMOS X-ray Detector User Manual
In this case, the Sync In pulse is driven high when the user activates the ‘Expose’ button for the
X-ray equipment. With the change of the Sync Out level the generator is informed that the
detector is ready to receive the X-ray emission and starts to irradiate, see
Figure 11
Continuous readout – External Edge Trigger Timing
19.1.3
Continuous Readout - External Duration Trigger
In Duration Trigger, the detector is triggered by an external signal, for example, a Pulse
Generator. The detector exposure time is defined by the width of the pulse. In SCap, this mode is
selected by using Configuration – External Trigger – External Duration Trigger and by following
these steps:
1
Before exposure, the detector is continuously reading dark frames from the sensor.
2
The end of the frame readout is reported by the pulses (T
BR
) coming from the SyncOuts with
an interval T
R/O
. T
D
indicates the delay between the end of T
BR
and the actual conclusion of
the frame readout.
3
The user activates the Expose button for the X-ray equipment.
4
When the generator is ready to produce X-rays, it waits for the next SyncOut 1 pulse from the
detector.
5
At the active (falling) edge of SyncOut 1, the generator drives SyncIn high while starting the
X-ray emission.
6
Once the external trigger signal drives SyncIn high, the current dark frame readout finishes
(T
R
) then the exposure period begins.
7
Immediately after the X-ray emission, the generator drives Sync In low. The detector reads
out the image and transmits it to the PC.
8
While Sync In is low, SyncOut 1 continues to pulse at interval T
R/O.
9
In Duration Trigger the SyncOut 2 changes its status when the detector is ready to expose
(trigger received, and sensor readout terminated).
