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Input Data Code
(Decimal)
3/256
PWM dimming duty
4/256
5/256
0
6/256
3 2 4 1 5
2
5
4
2
5
3
2
5
5
2
5
2
0
256/256
2
5
1
255/256
254/256
253/256
252/256
2/256
(Skipped)1/256
BIT7 BIT6 BIT5 BIT4 BIT3 BIT2 BIT1 BIT0
One data byte
DIM01
DIM23
(Clock signal)
(Data)
DIM01
DIM23
(Clock signal)
(Data)
BYTE1
(Group D)
BYTE2
(Group C)
BYTE3
(Group B)
BYTE4
(Group A)
DIM4
(End of Frame)
EOF
One data frame
LSB MSB
BOF
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PWM Dimming Control
Figure 9. Typical waveforms of a complete data frame in the serial interface mode
Figure 10. PWM dimming duty vs code value of a data byte
In the serial interface mode, the six output channels are grouped into four individual groups. The on duty
of each group is controlled by the value of a specific data byte as listed in the following table:
15 SNVA642 – May 2012 AN-2255 LM3463 Evaluation Board
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