Couple of begineer questions about Neopixels for a wordclock

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bug3
 
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Couple of begineer questions about Neopixels for a wordclock

Post by bug3 »

Hey guys,

I started building a wordclock with the great Neopixel stripes. So far - so good.
Finishing the electric circuit, there are arising a few questions now, I hope you can help me:

First:
I soldered one recommended 1000 µF capacitor between +5V and GND of the DC power supply.
The thing is: With 120 LEDs in 10 stripes, I have split the stripes into 5 parallel circuits (via busbars), like described here: https://learn.adafruit.com/adafruit-neo ... ting-power
Is it better to add one capacitor to each parallel branch - or should one capacitor at the power supply be sufficient (I hate soldering :D)?

Second:
When plugging the power supply in, all LEDs light up to full white for about half a second, until the microcontroller applies the signal. I'm worrying about the power supply: 4,5 A max. are a lot less than the current drawn by all LEDs fully lit up. Am I worrying too much?

Third - and last:
My microcontroller forwards the signal to all LEDs except the last 22 LEDs. Might this have sth. to do with the fact that I haven't built in a step-up converter from 3.3 V (controller) to 5 V yet? Or should the effect to the voltage difference be different?


Thanks indeed for your help!
Greetings from germany

bug

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Franklin97355
 
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Re: Couple of begineer questions about Neopixels for a wordc

Post by Franklin97355 »

For your setup and as a starting position one cap at the power supply should be OK. The power supply can only deliver what is can and for a short amount of time it should be OK. In the final project, you might consider having the micro control the power to the pixels through a MOSFET. Check to make sure your code is using the correct library calls, there are RGB and RGBW pixels and they take different amounts of data to control them.

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