CHEETAH Hardware User’s Manual
Imperx, Inc.
Rev. 6.2
6421 Congress Ave.
7/7/2015
Boca Raton, FL 33487
+1 (561) 989-0006
50 of 152
Figure 2.7 – Strobe positioning with respect to exposure start
2.10
VIDEO AMPLIFIER GAIN AND OFFSET
2.10.1 Analog Domain
– manual control
The camera takes advantage of the analog gain functionality built into the KAC-
12040 image sensor. The manufacturer recommends applying analog gain before
using the digital gain function. The image sensor automatically adjusts the black
level as the analog gain is adjusted to minimize fluctuation. The user adjustable
target black level is added after the gain stage and adjustments to this setting will not
impact dark level sensitivity. The analog gain is a non-linear function with smaller
gain adjustments when the gain is small and larger adjustments when the gain is
large. The gain range depends upon output bit depth with gains of 1 to 12dB possible
using 12-bit digitization and 1 to 18 dB possible using 10-bit digitization.
For 10-bit digitization, there are 15 different potential gain settings while 12-bit
digitization has 7 potential settings as described formula and table below:
10 Bit Digitization Gains:
Analog Gain = 16 / [(Select Code Bits (5:0)) / 2];
12-Bit Digitization:
Analog Gain = 8 / [(Select Code Bits (4:0)) / 2
Note: Bit 0 is always 0 and Select code =2 and gains less than 1 are not allowed.
Analog Gain Vs Select Code
Select
Code
10-Bit Gain
12-Bit Gain
4
8.00
4.00
6
5.33
2.67
8
4.00
2.00
10
3.20
1.60
