What I want is independent control of the 16 (or more) LEDs while removing most of the resources from the PIC side. If that makes any sense. I want to be able to still use the majority of the other I/O ports on the pic for other things while not being burdened by constantly controlling the 16 (or more) LEDs... Also the use of a driver chips increases the source/sink levels and allows me to limit all channels current with a single resistor. Lower parts count and smaller circuit size. I figure even for basic applications the single chip replaces darlington arrays and multiple current limiting resistors, lowering the parts count almost immediately.
As for the particular chips I mentioned only because I have those on hand, any 16 channel controller will work, not picky at all right now, and I'm open to other chips... The reason I want to go this way instead of multiplexing is the ability to cascade these chips and expand to lots of LEDs while not increasing the number of used I/O pins on the chip... If my understanding is correct, I should be able to control 100s of LED independently from even a pic16f628a with plenty of left over I/O lines by cascading the controller chips. Multiplexing directly off the pic in the end (unless I'm missing some trick) will incur substantially more parts and I/O lines as the number of LEDs increase.
Hope that clarifies things.
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