OV9625 Datasheet, PDF (3/30 Pages) List of Unclassifed Manufacturers – OV9625 Color CMOS SXGA (1.3 MPixel) CAMERACHIP OV9121 B&W CMOS SXGA (1.3 MPixel) CAMERACHIP

Omni ision
Functional Description
Image Sensor Array
The OV9625/OV9121 sensor is a 1/2-inch format CMOS
imaging device. The sensor contains 1,359,232 pixels.
Figure 3 shows the active regions of sensor array.
Figure 3 Sensor Array Region
Column
R
o0 B G B G B G
w_{1 G R G R G R}
2BG BG BG
3G R G R G R
4
5
6BG BG BG
7G R G R G R
8BG BG BG
9G R G R G R
10 B G B G B G
11 G R G R G R
1032 B G B G B G
1033 G R G R G R
1034 B G B G B G
1035 G R G R G R
BG BG BG
G RG RG R
BG BG BG
G RG RG R
BG BG BG
G RG RG R
BG BG BG
G RG RG R
BG BG BG
G RG RG R
BG BG BG
G RG RG R
BG BG BG
G RG RG R
Dummy
Dummy
Dummy
Dummy
Optical
Black
Dummy
Dummy
Dummy
Dummy
1024
Active
Lines
Dummy
Dummy
The color filters are Bayer pattern. The primary color
BG/GR array is arranged in line-alternating fashion. Of the
1,359,232 pixels, 1,310,720 are active. The other pixels
are used for black level calibration and interpolation.
The sensor array design is based on a field integration
read-out system with line-by-line transfer and an
electronic shutter with a synchronous pixel read-out
scheme.
Gain Control
When the column sample/hold circuit has sampled one
row of pixels, the pixel data will shift out one-by-one into
an analog amplifier. The amplifier gain can either be
programmed by the user or controlled by the internal
automatic gain control circuit (AGC). The gain adjustment
range is 0-24 dB.
Channel Balance
The amplified signals are then balanced with a channel
balance block. In this block, Red/Blue channel gain is
increased or decreased to match Green channel
luminance level and gamma correction is performed. The
adjustment range is 54 dB. This function can be done
manually by the user or with the internal automatic white
balance controller (AWB).
10-Bit Analog-to-Digital Converter
The balanced signal then will be digitized by the on-chip
10-bit ADC. It can operate at up to 12 MHz, and is fully
synchronous to the pixel clock. The actual conversion rate
is determined by the frame rate.
Black Level Compensation
After the pixel data has been digitized, black level
calibration can be performed before the data is output.
The black level calibration block subtracts the average
signal level of optical black pixels to compensate for the
dark current in the pixel output. Black level calibration can
be disabled by the user.
Windowing
OV9625/OV9121 allows the user to define window size or
region of interest (ROI), as required by the application.
Window size setting (in pixels) ranges from 2 x 4 to
1280 x 1024 (SXGA) or 2 x 2 to 640 x 480 (VGA), and can
be anywhere inside the 1312 x 1036 boundary. Note that
modifying window size or window position does not alter
the frame or pixel rate. The windowing control merely
alters the assertion of the HREF signal to be consistent
with the programmed horizontal and vertical ROI. The
default window size is 1280 x 1024. See Figure 4 and
registers HREFST, HREFEND, VSTRT, VEND, and
COMM for details. The maximum output window size is
1292 columns by 1024 rows.
Note that after writing to register COMH (0x12) to change
the sensor mode, registers related to the sensor’s
cropping window will be reset back to its default value.
Figure 4 Windowing
Column
Start
HREF
R ^Column
o
w
Column
End
Row Start
Row End
Display
Window
Sensor Array
Boundary
Version 1.3, September 15, 2003
Proprietary to OmniVision Technologies
3