MT9P031I12STM-ES Aptina LLC, MT9P031I12STM-ES Datasheet - Page 49

• Manufacturer Part Number: MT9P031I12STM-ES
• Manufacturer: Aptina LLC

Specifications of MT9P031I12STM-ES

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Signal Chain and Datapath
Figure 25:
Gain
Table 17:
Analog Gain
PDF: 09005aef81a4a477/Source: 09005aef81a4a495
MT9P031_DS - Rev. E 7/10 EN
Gain Range
4.25–8
9–128
1– 4
Gain Increment Settings
Signal Path
Note:
signal can be inverted by setting Invert_Strobe (R0x1E[5] = 1. To use strobe as a flash in
snapshot modes or with mechanical shutter, set the Strobe_Enable register bit field
R0x1E[4] = 1.
The signal chain and datapath are shown in Figure 25. Each color is processed indepen-
dently, including separate gain and offset settings. Voltages sampled from the pixel array
are first passed through an analog gain stage, which can produce gain factors between 1
and 8. An analog offset is then applied, and the signal is sent through a 12-bit analog-to-
digital converter. In the digital space, a digital gain factor of between 1 and 16 is applied,
and then a digital offset of between –2048 and 2047 is added. The resulting 12-bit pixel
value is then output on the D
The analog offset applied is determined automatically by the black level calibration
algorithm, which attempts to shift the output of the analog signal chain so that black is
at a particular level. The digital offset is a fine-tuning of the analog offset.
There are two types of gain supported: analog gain and digital gain. Combined, gains of
between 1 and 128 are possible. The recommended gain settings are shown in Table 17.
The combined gain for a color C is given by:
G
The analog gain is specified independently for each color channel. There are two
components, the gain and the multiplier. The gain is specified by Green1_Analog_Gain,
Red_Analog_Gain, Blue_Analog_Gain, and Green2_Analog_Gain in steps of 0.125. The
Voltage
C
Pixel
Increments
= AG
Analog gain should be maximized before applying digital gain.
0.125
0.25
1
C
x DG
Analog
Gain
X
C
.
Analog
Offset
+
Digital Gain
1–120
OUT
49
Analog Signal Chain
0
0
[11:0] ports.
MT9P031: 1/2.5-Inch 5Mp Digital Image Sensor
ADC
Analog Multipier
Digital Datapath
Calibration
Black
Level
Aptina reserves the right to change products or specifications without notice.
0
1
1
Digital
Gain
X
©2005 Aptina Imaging Corporation. All rights reserved.
Correction
Digital
Offset
+
Analog Gain
17–32
8–32
32
D
Features
OUT
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