LUPA-1300 CYPRESS [Cypress Semiconductor], LUPA-1300 Datasheet - Page 31

• Manufacturer Part Number: LUPA-1300
• Description: 1.3 M Pixel High Speed CMOS Image Sensor
• Manufacturer: CYPRESS [Cypress Semiconductor]

LUPA-1300
Datasheet
Figure 16: Timing of the x-shift register. The curves from bottom to top : Clock_x,
Sync_x, Internal generated Clock, Sel_block1, sel_block2,…
The timing in figure 16 is comparable with the timing of the y-shift register, only that
the timing is much faster. Again the synchronization pulse must be high on the rising
edge of Clock_x.
IMPORTANT note : The applied Clock_x, is filtered on chip to remove spikes. This
is especially required at these high speeds. This filtering results in an on chip
Clock_x that is delayed in time with about 10nsec. In other words, the data at the
output has, with respect to the external Clock_x, a propagation delay of 20nsec. This
20nsec come from 10nsec of the generation of the internal Clock_x and 10nsec due to
other on chip generated signals.
4.2.1 Reduced Row Overhead Time timing
The row overhead time is the time between the selection of lines that one has to wait
to get the data stable at the column amplifiers.
This row overhead time is a loss in time, which should be reduced as much as
possible.
4.2.1.1 Reduced timing
A straightforward way of reducing the R.O.T is by using a sample and hold function.
By means of Sh_col the analog data is tracked during the first 200nsec during the
selection of a new set of lines. After 200nsec, the analog data is stored. The ROT is
in this case reduced to 200nsec, but as the internal data was not stable yet dynamic
range is lost because not the complete analog levels are reached yet after 200ns.
Figure 17 shows this principle. Sh_col is now a pulse of 100ns-200ns starting 25 ns
after Norowsel. The duration of Sh_col is equal to the ROT. The shorter this time the
shorter the ROT will be however this lowers also the dynamic range.
Cypress Semiconductor Corporation
3901 North First Street
San Jose, CA 95134
408-943-2600
Contact [e-mail]
Document # : 38-05711 Rev.**( Revision 3.1)
Page 31 of 48