MT9P031 Datasheet, PDF (32/46 Pages) List of Unclassifed Manufacturers – 1/2.5-Inch 5Mp CMOS Digital Image Sensor

MT9P031: 1/2.5-Inch 5Mp Digital Image Sensor
Features
Operating Modes
The exposure time is calculated by determining the reset time of each pixel row (with
time 0 being the start of the first row time), and subtracting it from the sample time.
Under normal conditions in ERS modes, every pixel should end up with the same expo-
sure time. In global shutter release modes, or in row binning modes, the exposure times
of individual pixels can vary.
In global shutter release modes (described later), exposure time starts simultaneously
for all rows, but still ends as defined above. In a real system, the exposure would be
stopped by a mechanical shutter, which would effectively stop the exposure to all rows
simultaneously. Each output row's exposure time will differ by ^tROW from the previous
row because this specification does not consider the effect of an external shutter .
Global shutter modes also introduce a constant added to the shutter time for each row,
because the exposure starts during the global shutter sequence, and not during any
row's shutter sequence. For each additional row in a row bin, this offset will increase by
the length of the shutter sequence.
In Bulb_Exposure modes (see details in Table 13), the exposure time is determined by
the width of the TRIGGER pulse rather than the shutter width registers. In ERS bulb
mode, it is still a multiple of row times, and the shutter overhead equation still applies. In
GRR bulb mode, the exposure time is granular to ACLKs, and shutter overhead (and thus
Shutter_Delay) has no effect.
In default operating mode, the MT9P031 continuously samples and outputs frames. It
can be put in "snapshot" or triggered mode by setting snapshot, which means that it
samples and outputs a frame only when triggered. To leave snapshot mode, it is neces-
sary to first clear Snapshot then issue a restart.
When in snapshot mode, the sensor can use the ERS or the GRR. The exposure can be
controlled as normal, with the Shutter_Width_Lower and Shutter_Width_Upper regis-
ters, or it can be controlled using the external TRIGGER signal. The various operating
modes are summarized in Table 13.
Table 13: Operating Modes
Mode
ERS Continuous
ERS Snapshot
ERS Bulb
GRR Snapshot
GRR Bulb
Settings
Default
Snapshot = 1
Snapshot = 1;
Bulb_Exposure = 1
Snapshot = 1;
Global_Reset = 1
Snapshot = 1;
Bulb_Exposure = 1;
Global_Reset = 1
Description
Frames are output continuously at the frame rate defined by ^tFRAME. ERS is used, and the
exposure time is electronically controlled to be ^tEXP.
Frames are output one at a time, with each frame initiated by a trigger. ERS is used, and the
exposure time is electronically controlled to be ^tEXP.
Frames are output one at a time, with each frame's exposure initiated by a trigger. ERS is used.
End of exposure and readout are initiated by a second trigger.
Frames are output one at a time, with each frame initiated by a trigger. GRR is used. Readout is
electronically triggered based on SW.
Frames are output one at a time, with each frame initiated by a trigger. GRR is used. Readout is
initiated by a second trigger.
Note: In ERS bulb mode, SW must be greater than 4 (use trigger wider than ^tROW * 4).
All operating modes share a common set of operations:
1. Wait for the first trigger, then start the exposure.
2. Wait for the second trigger, then start the readout.
PDF: 09005aef81a4a477/Source: 09005aef81a4a495
MT9P031_DS - Rev. F 5/11 EN
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©2005 Aptina Imaging Corporation. All rights reserved.