Oki OKIPAGE 10ex Maintenance Manual page 40

The LED driver (MSM6731BWAF) corrects the LED illumination by controlling the LED current.
The LED illumination can be set in 16 steps, with 7 steps in the direction of illumination increase
in relation to the standard value, and 8 steps in the direction of decrease. For this reason, the LED
correction data is a 4-bit data for each dot.
The relationship between the LED correction data and LED current correction steps with the LED
driver (MSM6731BWAF) used in an LED head is shown below.
msb b3
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
LED Correction Data
Correction Data
b2 b1 lsb b0
0 0
1 1
1 1
1 0
1 0
0 1
0 1
0 0
0 0
1 1
1 1
1 0
1 0
0 1
0 1
0 0
2 - 25
Correction Correction
Step Mode
0 +16%
1 +14%
0 +12%
Correction by
1 +10%
increasing
0 +8% illumination
1 +6%
0 +4%
1 +2%
0 0% No correction
1 -2%
0 -4%
1 -6% Correction by
0 -8% decreasing
1 -10% illumination
0 -12%
1 -14%