Andor Technology Zyla sCMOS 5.5 - Rolling Shutter External Exposure Triggering (Non-Overlap Mode)

version 2.0 rev 18 Feb 2021
36
2.6.2.6 Rolling Shutter External Exposure Triggering (Non-Overlap Mode)
While waiting on the trigger event, the sensor held in a global clear state and is put into a “pre-scan read out
cycle”. On detection of the trigger event, Global Clear goes LOW and a frame read out is initiated. This frame
isdiscardedasitdoesnotcontainthecorrectexposureperiod.Readingoutaframeeectivelybeginsanew
exposure. When the external trigger input goes LOW, a signal frame read out phase begins. When the frame
has been read out completely, the Global Clear is held HIGH until the next trigger event is detected.
Theexternaltriggerpulsewidthdenestheexposuretimeforallrows,butisonlycoincidentwiththeexposure
time for Row 1. The exposure for Row 2 will be delayed by one row time relative to Row 1 and so forth.
Theperiodoftheexternaltriggerpulsedenestheoverallcycletime.Ifthewidthofthetriggereventis
less than 3 Rows, the falling edge will be missed and a subsequent falling edge will be required to end the
exposure.
Figure20:Rolling Shutter External Exposure Triggering (Non Overlap Mode)
Table 16: Rolling Shutter External Exposure Triggering (Non Overlap Mode) Timing Parameters
Parameter Minimum Maximum
Exposure 3 Rows 30 s
Cycle Time (EXT Trig Period) Exposure + 1 Frame + 1 Row -
External Start Delay 0 1 Row
EXT Trig Pulse Width 3 Rows 30 s