24-Output PWM LED Drivers
for Message Boards
two external pnp transistors, such as FMMTL717, used
as common-anode power switches (see Figure 5).
Setting configuration bit D0 to 1 enables multiplex
operation. MUX0 and MUX1 alternate the LED anode
drive voltage between two sets of LEDs. The R, G, and
B ports provide individual PWM control during alternate
Figure 5. MAX6975 Multiplexing Two Sets of Eight RGB Pixels with a Single LED Supply and Subframe Timing
12 ______________________________________________________________________________________