CAT4103 Datasheet, PDF (10/13 Pages) ON Semiconductor – 3-Channel Constant-Current RGB LED Driver

CAT4103
Application Information
Cascading Multiple Devices
The CAT4103 is designed to be cascaded for driving
multiple RGD LEDs. Figure 16 shows three CAT4103
drivers cascaded together. The programming data from the
controller travels serially through each device. Figure 15
shows a programming example turning on the following
LED channels: BLUE3, GREEN2 and RED1. The
programming waveforms are measured from the controller
to the inputs of the first CAT4103.
Figure 15. Programming Example
5 V _C1
1 mF
RED1 GREEN1 BLUE1
VDD LED1 LED2 LED3
BIN
BOUT
LIN
C AT4103
LOUT
SIN
#1
SOUT
CIN
COUT
GND RSET1 RSET2 RSET3
C2
1 mF
RED2 GREEN2 BLUE2
VDD LED1 LED2 LED3
BIN
BOUT
LIN
C AT4103
LOUT
SIN
#2
SOUT
CIN
COUT
GND RSET1 RSET2 RSET3
C3
1 mF
RED3 GREEN3 BLUE3
VDD LED1 LED2 LED3
BIN
BOUT
LIN
C AT4103
LOUT
SIN
#3
SOUT
CIN
COUT
GND RSET1 RSET2 RSET3
R1
R2
R3
R4
R5
R6
R7
R8
R9
Figure 16. Three Cascaded CAT4103 Devices
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