IBIS4-6600 Datasheet, PDF (26/63 Pages) Cypress Semiconductor – High resolution 6.6 M Pixel Rolling shutter CMOS Image sensor

IBIS4-6600
Datasheet
3.8 High dynamic range modes
3.8.1 Double slope integration
The IBIS4-6600 has a feature to increase the optical dynamic range of the sensor;
called double slope integration. The pixel response can be extended over a larger
range of light intensities by using a “dual slope integration” (patents pending). This is
obtained by the addition of charge packets from a long and a short integration time in
the pixel during the same exposure time.
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
0%
Dual slope operation
Long integration time
Short integration time
10%
20%
30%
40%
50%
Relative exposure (arbitrary scale)
60% 70% 80% 90% 100%
Figure 16: Double slope response curve
Figure 16 shows the response curve of a pixel in dual slope integration mode. The
curve also shows the response of the same pixel in linear integration mode, with a
long and short integration time, at the same light levels.
Dual slope integration is obtained by:
Feeding a lower supply voltage to VDD_RESET_DS (e.g. apply 2.0V to
2.5V). Note that for normal (single slope operation VDD_RESET_DS should
have the same value as VDD_RESET. The difference between
VDD_RESET_DS and VDD_RESET determines the range of the high
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Contact: [e-mail] Document #: 38-05708 Rev.**(Revision 1.3 )
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