CYII5FM1300AB_09 Datasheet, PDF (7/41 Pages) Cypress Semiconductor – 1.3 MP CMOS Image Sensor

IBIS5-B-1300 CYII5FM1300AB
X-Addressing
Because of the high pixel rate, the X-shift register selects two
columns at a time for readout, so it runs at half the system clock
speed. All even columns are connected to bus A; all odd columns
to bus B. In the output amplifier, bus A and bus B are combined
into one stream of pixel data at system clock speed.
At the end of the row blanking time, the X_SYNC switch is closed
while all other switches are open and the decoder output is fed
to the register. The decoder loads a logical one in one of the
registers and a logical zero in the rest. This defines the starting
point of the window in the X direction. As soon as the X_SYNC
signal is released, the register starts shifting from the start
position.
When no sub-sampling is required, X_SUB is inactive. The
pointer in the shift-register moves one bit at a time.
When sub-sampling is enabled, X_SUB is activated. The shift
register moves two bits at a time. Taking into account that every
register selects two columns, hence two pixels sub-sampling
results in the pattern ’XXOOXXOO’ when eight pixels are
considered. Suppose the columns are numbered from left to right
starting with 0 (zero) and sub-sampling is enabled:
If columns 1 and 2, 5 and 6, 9 and 10 … are swapped using the
SWAP_12 switches, a normal sub-sampling pattern of
’XOXOXOXO’ is obtained.
If columns 3 and 4, 7 and 8, 11 and 12 … are swapped using the
SWAP_30 switches, the pattern is ’OXOXOXOX’.
If both the SWAP_12 and SWAP_30 switches are closed, pattern
’OOXXOOXX’ is obtained.
Because every register addresses two columns at a time, the
addressable pixels range in sub-sample mode is from zero to half
the maximum number of pixels in a row (only even values). For
instance: 0, 2, 4, 6, 8… 638.
Table 6. X–Sub-sample Patterns
X_SUB
0
1
1
X_SWAP12 X_SWAP30 Sub-Sample Pattern
0
0
XXXXXXXX
0
0
XXOOXXOO
1
0
XOXOXOXO
1
0
1
OXOXOXOX
1
1
1
OOXXOOXX
Y-addressing
For symmetry reasons, the sub-sampling modes in the
Y-direction are the same as in X-direction.
Table 7. Y–Sub-Sample Patterns
Y_SUB
0
1
1
1
1
Y_SWAP12 Y_SWAP30 Sub-Sample Pattern
0
0
XXXXXXXX
0
0
XXOOXXOO
1
0
XOXOXOXO
0
1
OXOXOXOX
1
1
OOXXOOXX
Figure 6. Column Structure
COL(i)
COL(i+2)
COL(i+1)
COL(i+3)
X_SWAP30
X_SWAP12
BUS_A
BUS_B
AB
AB
AB
Reg(n)
Reg(n+1)
Reg(n+2)
SYS_CLOCK 1/2
Column
amplifiers
Output
amplifier
X_SUB
X_SYNC
Document #: 38-05710 Rev. *E
DEC(n+1) DEC(n+2)
Page 7 of 41
[+] Feedback