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Topic: 7 segment shift register backpack (Read 1 time) previous topic - next topic

bld

I am trying to make a PCB to solder my 2.3" 7 segment displays onto.

The PCB holds a 74HC595 shift register and a ULN2803A to drive the display.

The idea is that I can have multiple of these PCB's, and just put them after each other in a long line. And add more without really doing anything to the hardware.


My problem is now that I don't have that great experience with making PCB's, and first time ever I am going to try shift registers, so I would be happy if someone would take a look over what I have made, and maybe spot an error.

I know the schematic is a big messy, but still learning how to do it better.
captain-slow.dk | non contagious!

mowcius


Grumpy_Mike


bld


Put some decoupling capacitors on the shift register.
http://www.thebox.myzen.co.uk/Tutorial/De-coupling.html

Been over that page, trying to figure out what to do...

Added a 0.1uF as close to the vcc pin as possible. But where should there be others? Guess there should be more than just one since you said capacitors?
captain-slow.dk | non contagious!

Grumpy_Mike

I would put a place for a 10uF capacitor on each board where the power goes in. However you will probably not have to fit one on every board just one on the first in the chain and the last.

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