mt9v034c12stmdes aptina, mt9v034c12stmdes Datasheet - Page 58

• Manufacturer Part Number: mt9v034c12stmdes
• Description: 1/3-inch Wide-vga Cmos Digital Image Sensor
• Manufacturer: aptina

Analog Gain
Digital Gain
PDF: 09005aef8366edcb/Source: 09005aef8366ede5
MT9V034_DS - Rev. A 10/08 EN
Note:
Analog gain is controlled by:
• R0x35 Global Gain context A
• R0x36 Global Gain context B
The formula for gain setting is:
The analog gain range supported in the MT9V034 is 1X
6.25 percent. To control gain manually with this register, the sensor must NOT be in AGC
mode. When adjusting the luminosity of an image, it is recommended to alter exposure
first and yield to gain increases only when the exposure value has reached a maximum
limit.
For values 16–31: each LSB increases analog gain 0.0625v/v. A value of 16 = 1X gain.
Range: 1X to 1.9375X.
For values 32–64: each 2 LSB increases analog gain 0.125v/v (that is, double the gain
increase for 2 LSB). Range: 2X to 4X. Odd values do not result in gain increases; the gain
increases by 0.125 for values 32, 34, 36, and so on.
Digital gain is controlled by:
• R0x99-R0xA4 Tile Coordinates
• R0x80-R0x98 Tiled Digital Gain and Weight
In the MT9V034, the gain logic divides the image into 25 tiles, as shown in Figure 25 on
page 59. The size and gain of each tile can be adjusted using the above digital gain
control registers. Separate tile gains can be assigned for context A and context B.
Registers 0x99–0x9E and 0x9F–0xA4 represent the coordinates X0/5–X5/5 and Y0/5–Y5/5
in Figure 25 on page 59, respectively.
Digital gains of registers 0x80–0x98 apply to their corresponding tiles. The MT9V034
supports a digital gain of 0.25–3.75X.
When binning is enabled, the tile offsets maintain their absolute values; that is, tile coor-
dinates do not scale with row or column bin setting.
The formula for digital gain setting is:
Analog gain = bits (6:0) x 0.0625 for values 16–31
Analog gain = bits (6:0)/2 x 0.125 for values 32–64
There is one exception, for the condition when Column Bin 4 is enabled (R0x0D[3:2]
or R0x0E[3:2] = 2). For this case, the value for Digital Tile Coordinate
X–direction must be doubled.
Digital Gain = Bits[3:0] x 0.25
Aptina Confidential and Proprietary
Gain = Bits[6:0] x 0.0625
58
MT9V034: 1/3-Inch Wide-VGA Digital Image Sensor
Aptina Imaging reserves the right to change products or specifications without notice.
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4X with a step size of
©2008 Aptina Imaging Corporation. All rights reserved.
Feature Description
(EQ 17)
(EQ 18)