user56674: I'm new here and I'm a newbie in electronics. Since 1 year I'm playing around with Arduino (different types) and now I want to build my own thing: a smiley with WS2812D-F5 RGB leds. But I'm not sure if I did any misstakes. Is it possible that an expert in electronics can check my schematic? That would be very kind, nice and cool :)
Functions: The switch SW1 is connected on D8 (PB4) and if pushed the smiley changes from sad to happy. pushed again it changes again and so on. 
Because the WS2812 leds needs a lot of current, I have added some different possibilities to power the whole thing: 1x DC jack connected on a voltage regulator that output 5V fixed and two pins for a LiPo 3.7V that ist connected too on the voltage regulator. I dont know if it works if the LiPo has only 3.7V.
Well.. then I added a power switch, micro usb, FTDI and SPI connection. If one fails to burn the bootloader or to upload a sketch, I have more possibilities to do that ;)
Yeah I think thats it. If I forgot something, just ask me. Thanks a lot!
Kind regards. 
Greetings from Switzerland
delf

Edit 15.5.19 18:00
Ok, I just changed the schematic based upon your great advices :) Thanks a lot to everyone. I changed/added the regulator. Current output=3A (each one). Should  be enough. But I'm not sure if I can divide the current in that way.
What do you think? :)
Greetings to everyone :)


user4143: No. That circuit will not work.
The moment you turn on more than a few of the LEDs the regulator will go into meltdown. No matter how powerful your power supply is, that regulator is the bottleneck and will overheat the moment you try and light your smiley face.
The regulator (a venerable 7805 - I mean, come on, that's from the ark. There's far better modern regulators now...) is rated for a maximum of 1A. That is with very good heatsinking and thermal management, and an input voltage only slightly above 5V + the dropout voltage.  Your circuit can draw up to about 4A. That's 4x what the regulator is rated for when it's at its most optimim - probably 6x to 8x what your arrangement would be able to provide.
For this kind of circuit you need a switching regulator. One that can provide many many times the current of a linear regulator like the 7805 (or the more modern LM1117-5.0).  You need one that will provide at least 4A, and ideally a little more for some extra headroom. So you're looking at 5A.
With a decent efficiency you could then run the whole thing from a 12V input with 2.5A minimum current. Assuming 85% efficiency:

12V @ 2.5A = 30W
85% of 30W = 25.5W
25.5W @ 5V = 5.1A

So a 12V, 2.5A supply being fed into a 5V, 5A switching regulator with at least 85% efficiency will allow your circuit to operate more reliably.
You also need to take care with your PCB layout (assuming you are designing this for building on a PCB). Switching regulators take a certain amount of care when laying them out. You should refer to the recommended PCB layout in the datasheet for your chosen regulator and stick as closely to that as you can.
Also handling larger currents requires more thought put into your traces.  This site has a handy trace width calculator.
As an example: for a 5A trace over a distance of 5cm with (standard) 1oz copper your trace should be at least 2.77mm wide. That will give a 10C temperature rise in the trace at room temperaure (25C to 35C).

56674: <p>I'm new here and I'm a newbie in electronics. Since 1 year I'm playing around with Arduino (different types) and now I want to build my own thing: a smiley with WS2812D-F5 RGB leds. But I'm not sure if I did any misstakes. Is it possible that an expert in electronics can check my schematic? That would be very kind, nice and cool :)</p>

<p>Functions: The switch SW1 is connected on D8 (PB4) and if pushed the smiley changes from sad to happy. pushed again it changes again and so on. </p>

<p>Because the WS2812 leds needs a lot of current, I have added some different possibilities to power the whole thing: 1x DC jack connected on a voltage regulator that output 5V fixed and two pins for a LiPo 3.7V that ist connected too on the voltage regulator. I dont know if it works if the LiPo has only 3.7V.</p>

<p>Well.. then I added a power switch, micro usb, FTDI and SPI connection. If one fails to burn the bootloader or to upload a sketch, I have more possibilities to do that ;)</p>

<p>Yeah I think thats it. If I forgot something, just ask me. Thanks a lot!</p>

<p>Kind regards. </p>

<p>Greetings from Switzerland</p>

<p>delf
<a href="https://i.stack.imgur.com/HNfG5.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HNfG5.png" alt="Schematic WS2912 atmega32u4 smiley"></a></p>

<p>Edit 15.5.19 18:00
Ok, I just changed the schematic based upon your great advices :) Thanks a lot to everyone. I changed/added the regulator. Current output=3A (each one). Should  be enough. But I'm not sure if I can divide the current in that way.</p>

<p>What do you think? :)</p>

<p>Greetings to everyone :)</p>

<p><a href="https://i.stack.imgur.com/Pw1vh.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Pw1vh.png" alt="Version 1.2"></a></p>
 4143: <p>No. That circuit will not work.</p>

<p>The moment you turn on more than a few of the LEDs the regulator will go into meltdown. No matter how powerful your power supply is, that regulator is the bottleneck and will overheat the moment you try and light your smiley face.</p>

<p>The regulator (a venerable 7805 - I mean, come on, that's from the ark. There's far better modern regulators now...) is rated for a maximum of 1A. That is with <em>very good heatsinking and thermal management, and an input voltage only slightly above 5V + the dropout voltage</em>.  Your circuit can draw up to about 4A. That's 4x what the regulator is rated for when it's at its most optimim - probably 6x to 8x what your arrangement would be able to provide.</p>

<p>For this kind of circuit you <em>need</em> a switching regulator. One that can provide many many times the current of a linear regulator like the 7805 (or the more modern LM1117-5.0).  You need one that will provide at least 4A, and ideally a little more for some extra headroom. So you're looking at 5A.</p>

<p>With a decent efficiency you could then run the whole thing from a 12V input with 2.5A minimum current. Assuming 85% efficiency:</p>

<ul>
<li>12V @ 2.5A = 30W</li>
<li>85% of 30W = 25.5W</li>
<li>25.5W @ 5V = 5.1A</li>
</ul>

<p>So a 12V, 2.5A supply being fed into a 5V, 5A switching regulator with at least 85% efficiency will allow your circuit to operate more reliably.</p>

<p>You also need to take care with your PCB layout (assuming you are designing this for building on a PCB). Switching regulators take a certain amount of care when laying them out. You should refer to the recommended PCB layout in the datasheet for your chosen regulator and stick as closely to that as you can.</p>

<p>Also handling larger currents requires more thought put into your traces.  <a href="https://www.7pcb.com/trace-width-calculator.php" rel="nofollow noreferrer">This site</a> has a handy trace width calculator.</p>

<p>As an example: for a 5A trace over a distance of 5cm with (standard) 1oz copper your trace should be at least 2.77mm wide. That will give a 10C temperature rise in the trace at room temperaure (25C to 35C).</p>
