MT9T031C12STC Aptina LLC, MT9T031C12STC Datasheet - Page 35

• Manufacturer Part Number: MT9T031C12STC
• Description: IC SENSOR IMAGE COLOR 48CLCC
• Manufacturer: Aptina LLC
• Series: Micron®DigitalClarity®r
• Type: CMOS Imagingr

Specifications of MT9T031C12STC

• Pixel Size: 3.2µm x 3.2µm
• Active Pixel Array: 2048H x 1536V
• Frames Per Second: 12 ~ 93
• Voltage - Supply: 3 V ~ 3.6 V
• Package / Case: 48-CLCC
• Brief Features: Superior Low Light Performance, Programmable Controls, Low Dark Current, High Frame Rate
• Supply Voltage Range: 3V To 3.6V
• Operating Temperature Range: 0°C To +60°C
• Ic Function: Digital Image Sensor
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 557-1450 - KIT HEAD BOARD FOR MT9T031557-1451 - KIT DEV FOR MT9T031
• Lead Free Status / Rohs Status: Compliant
• Other names: 557-1452

Gain Settings
Table 13:
Black Level Calibration
Manual Black Level Calibration
PDF: 3682685119/Source: 9830567334
MT9T031_DS - Rev.E 5/11 EN
Gain Increment Settings
R0x2B, R0x2C, R0x2D, R0x2E, and R0x35
The analog programmable gain stage consists of two stages of gain circuitry that operate
in a pipelined manner. The first stage of gain has programmable gain of 1 or 2 while the
second stage of gain has programmable gain of 1 to 4 with steps of 0.125 for a maximum
analog gain of 8. The gain settings can be independently adjusted for the colors of
Green1, Blue, Red, and Green2 and are programmed through R0x2B, R0x2C, R0x2D, and
R0x2E, respectively. The gain may also be adjusted globally through R0x35. The first
stage of gain is set by Bit(6), while the second stage gain is set by Bit(5
individually controllable for each color in the Bayer pattern as follows:
Analog Gain < = 8:
Gain = (Bit[6] + 1) x (Bit[5:0] x 0.125)
Digital Gain = 1 + Bit[14:8]/8
Total Gain = Analog Gain x Digital Gain
Since Bit[6] of the gain registers are multiplicative factors for the gain settings, there are
alternative ways of achieving certain gains. Some settings offer superior noise perfor-
mance to others, despite the same overall gain, as shown in Table 13.
R0x5D, and R0x5F
The digitized black level of the MT9T031 sensor potentially varies with temperature or
gain setting changes. The MT9T031 sensor allows the user the flexibility of automatic
black level calibration or manual black level control.
R0x60, R0x61, R0x62, R0x63, and R0x64
The programmable analog offset stage corrects for analog offset that might be present in
the analog signal. The user would need to program R0x62 appropriately to enable the
analog offset correction. The analog offset settings can be independently adjusted for
the colors of Green1, Green2, Red and Blue and are programmed through R0x60, R0x61,
R0x63 and R0x64 respectively. Bit[8] of R0x60, R0x61, R0x63 and R0x64 (these registers
have two’s complement representation) determines the sign of the analog offset. Bit[8] =
1 makes the analog correction negative instead of positive.
The lower 8 bits (Bit[7:0]) determine the absolute value of the analog offset to be
corrected and Bit[8] determines the sign of the correction. When Bit[8] is “1”, the sign of
the correction is negative and vice versa. The analog value of the correction relative to
the analog gain stage can be determined from the following formula:
Nominal Gain
4.25 to 8.00
9.0 to 128.0
1 to 4.000
35
MT9T031: 1/2-Inch 3-Mp Digital Image Sensor
Increments
0.125
0.25
1.0
©2006 Aptina Imaging Corporation. All rights reserved.
Recommended Settings
0x0008 to 0x0020
0x0051 to 0x0060
0x0160 to 0x7860
Feature Description
–
0). The gain is