IBIS4-A-6600 Datasheet, PDF (19/40 Pages) Cypress Semiconductor – 6.6 MP CMOS Image Sensor

ADVANCE
INFORMATION
IBIS4-A-6600
CYII4SM6600AB
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0
0%
Figure 15. Double Slope Response
20%
40%
Dual slope operation
Long integration time
Short integration time
Relative exposure (arbitrary scale)
60%
80%
100%
Non-destructive Read Out (NDR)
The default mode of operation of the sensor is with FPN
correction (double sampling). However, the sensor can also be
read out in a non-destructive way. After a pixel is initially reset,
it can be read multiple times, without resetting. The initial reset
level and all intermediate signals can be recorded. High light
levels will saturate the pixels quickly, but a useful signal is
obtained from the early samples. For low light levels, one has
to use the later or latest samples. Essentially an active pixel
array is read multiple times, and reset only once. The external
system intelligence takes care of the interpretation of the data.
Table 14. summarizes the advantages and disadvantages of
non-destructive readout.
Figure 16. Principle of Non-destructive Readout
time
Table 14. Pros and Cons of NDR
Advantages
Low noise - as it is true CDS. In the order of 10 e- or below.
High sensitivity - as the conversion capacitance is kept rather
low.
High dynamic range - as the results includes signal for short
and long integrations times.
Disadvantages
System memory required to record the reset level and the
intermediate samples.
Requires multiples readings of each pixel, thus higher data
throughput.
Requires system level digital calculations.
Document Number: 001-02366 Rev. *D
Page 19 of 40
[+] Feedback