IBIS4-6600 Datasheet, PDF (25/63 Pages) Cypress Semiconductor – High resolution 6.6 M Pixel Rolling shutter CMOS Image sensor

IBIS4-6600
Datasheet
3.7 Electronic shutter
A curtain like (rolling) electronic shutter has been implemented on chip. As can be
seen in Figure 14, there are two Y shift registers. One of them points to the row that is
currently being read out. The other shift register points to the row that is currently
being reset. Both pointers are shifted by the same Y-clock and move over the focal
plane. The integration time is set by the delay between both pointers.
Readout
pointer
Reset
pointer
Figure 14: Operation of the electronic shutter
In case of a mechanical shutter, the two shift registers can be combined to apply the
pulses from both sides of the pixel array simultaneously. This is to halve the influence
of the parasitic RC times of the reset and select lines in the pixel array (which can
result in a reduction of the row blanking time). This is the case when FAST_RESET in
the SEQUENCER register is set to 1 or in the non-destructive readout modes 1 and 2.
Line number
Reset sequence
Frame time
Time axis
Integration time
Figure 15: Rolling shutter operation
In Figure 15, we schematically indicate the relative shift of the integration times of
different lines during the rolling shutter operation. Each line is read and reset in a
sequential way. The integration time is the same for all lines, but shifted in time. The
integration time can be varied through the INT_TIME register (in number of lines).
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408-943-2600
Contact: [e-mail] Document #: 38-05708 Rev.**(Revision 1.3 )
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