LUPA-4000 Datasheet, PDF (13/49 Pages) Cypress Semiconductor – 4M Pixel CMOS Image Sensor

LUPA-4000
Data Sheet
3.2 Frame rate and windowing
3.2.1 Frame rate
To obtain a frame rate a 15 frames /sec, one needs 1 output amplifier, working at
66MHz pixel rate or 2 output amplifiers working at 33MHz each (assuming a Row
Overhead Time (ROT) of 200nsec).
The frame period of the LUPA-4000 sensor can be calculated as follows:
Frame period = FOT + (Nr. Lines * (ROT + pixel period * Nr. Pixels)
with:
FOT: Frame Overhead Time = 5 us.
Nr. Lines: Number of Lines read out each frame (Y).
Nr. Pixels: Number of pixels read out each line (X).
ROT: Row Overhead Time = 200 ns (nominal; can be further reduced).
Pixel period: 1/66 MHz = 15.15 ns.
Example read out of the full resolution at nominal speed (66 MHz pixel rate):
Frame period = 5 us + (2048 * (200 ns + 15.15 ns * 2048) = 64 ms => 15 fps.
3.2.2 ROI read out (windowing)
Windowing can easily be achieved by a serial–parallel uploadable interface in which
the starting point of the x- and y-address is uploaded. This downloaded starting point
initiates the shift register in the x- and y-direction triggered by the Sync_x and Sync_y
pulse. The minimum step size for the x-address and the y-address is 2 (only even start
addresses can be chosen). The size of both address registers is 10 bits. When for
instance the addresses 0000000001 and 0000000001 are uploaded, the readout will
start at line 2 and column 2.
Table 5: Frame rate as function of ROI read out and/or sub sampling
Image Resolution
(X*Y)
2048 x 2048
1024 x 2048
1024 x 1024
640 x 480
Frame rate
[frames/s]
15
31
62
210
Frame readout Comment
time [ms]
67
Full resolution.
32
Subsample in X-direction.
16
ROI read out.
4.7
ROI read out.
Cypress Semiconductor Corporation
3901 North First Street
San Jose, CA 95134
408-943-2600
Contact: [e-mail] Document #: 38-05712 Rev.**(Revision 1.2 )
Page 13 of 49