Author Topic: [Arduino] Multiplexing Questions  (Read 1255 times)

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Offline ArcadeTVTopic starter

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[Arduino] Multiplexing Questions
« on: February 02, 2015, 01:46:23 pm »
Hey Guys,
I'm building a switchbox for video-signals using an Arduino Mega2560 for development and SN74CBT3245CDWR fet switches to select between my different inputs.
Everything looks good and now I want to multiplex my logic to save some pins on the microcontroller.
Since I never intentionally used shift registers in my projects I'm a total n00b on this matter  :phew:

I'll have 20 channels, so there're 20 ICs and 20 LEDs.
I'm unsure about which shift registers to use, I've read that the 74HC595 may not be the best choice for dealing with LEDs.
The digital switch ICs will be enabled by their /OE pin, so I guess there shouldn't be an issue with current with those...
I may chose a TLC5940 for LEDs - anybody willing to suggest an alternative?

This is the basic schematic, a mockup of how I suspect that I'll wire my proto:



Please let me know if you consider this a bad setup or find any mistakes please.
The ICs' OutputEnable pins are active low, shall I use pullup-resistors just in case?

Thanks! Any help is as always very much appreciated!
« Last Edit: February 02, 2015, 01:53:05 pm by ArcadeTV »
 


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