Soldering WS2812b leds

HI.

I need to solder 32 WS2812b leds in a row.

https://cdn-shop.adafruit.com/datasheets/WS2812B.pdf

3 Questions.

1- I should solder "data in" of one led to "data out" of the next one with the MCU pin conected to "data in" side of the strip, and all Volt to same line and all Ground to same line...Right?

2- Do I need to solder any resistance or something?

Thanks.

Each Power and GND pin have a 100nF capacitor.

Data Out of the first pixel goes to the Data In pin of the second pixel etc.

The very first Data In pin should have a series 470 Ω resistor.

Thanks for the answer.

Each Power and GND pin have a 100nF capacitor.

I just have the leds. So I need to get them
I will not use a board.
I dont understand how those capacitors should be connected.

Solder them at the start of each strip.

Have you got individual surface mount LEDs or LEDs mounted on a very small board?

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Between GND and VCC (just saying)

Yes you will you will, either on each LED or a board of sorts. These are surface mount LEDs so you can't wire them in free space.
Each of these LEDs require a surface mount ceramic 0.1uF capacitor across the power and ground as well as the 100uF at the start of the strip.
Here are some pictures of mounting them on a double strip of self adhesive copper, wrapped round a circular box.
This is the box and copper, the hole is so they can be shining into the inside of the box.


This is how I wired them

This is how the wiring looked with the LEDs held physically in place with silicone sealant.

You can get the LEDs on a very small board with the LEDs and capacitor on the board. I soldered them together to form an LED strip in a wooden train set.

Thank you. Very useful!!!

Have you got individual surface mount LEDs or LEDs mounted on a very small board?

Just the leds

Is there any differnece in wich leg of the capacitor I place on V and Ground?

Can I use this kind of capacitor?

https://www.didacticaselectronicas.com/index.php/componentes-pasivos/capacitores/ceramicos/capacitor-cer%C3%A1mico,-0-1uf,-50v-104-condensadores-capacitores-condensador-filtro-filtros-104-through-hole-detail

Well it is not the best and seems to be very expensive. I don't know the exchange rate on that page but these should be about $0.05 US at the most.

The problem is the long leads, they act as inductors and make them stop looking like a capacitor at higher frequencies. Something like this is better.
Surface Mount

No because these capacitors are not polarised, and if they were then they would not work. The large 1000uF capacitor are polarised and they work as a team with the ceramic ones. You need one ceramic one per LED and only one large capacitor per strip, if the strip is longer than about 12 or so LEDs.

Thank you.

The large capacitor is 1000 or 100 uf ? ( You mistyped one of those)

The small capacitors go on the V side of the led?

And I need a 500 resistance for the data line....right?

No.
Either will do, a short strip will only need 100uF but a longer might need 1000uF. It surprises beginners that some electronics is not calculated to the Nth decimal place. You can't have too much but you may have too little. You haven't said how long a strip you are going to make.

Sorry I don't understand you. The small capacitors go between the positive and negative supply rails, the closer to the actual LED as you can get them.

Well again anything between 200R and 500R will do. I tend to use 220R (that is 220 ohms).

Im going to make a 32 led strip, in less than a meter. So with 100uf its ok?

Sorry I don't understand you. The small capacitors go between the positive and negative supply rails, the closer to the actual LED as you can get them.

But is it indifferent on wich side of the led it is?

I actually use WS2812b's to stick them into small buttons that otherwise may not be illuminated.

Yes you can, but keep the leads as short as possible. For ceramic disk or poly-propylene, polarity is not an issues. For larger capacitors like 100uF or 1000uF that usually come as electrolytic capacitors, polarity is relevant, and if you connect them the wrong way round, they may explode (mind your eyes)

Suggest you use 470uF or larger.

Yes. You either have a short path to the positive on the LED or a short path to the negative. As it is the total path that matters, it is irrelevant which you chose.

Yes 470uF is a good compromise.

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Thank you all for your time.

Last stupid one.

The 470 uf capacitor goes V to V and G to G....right? Just in case

The positive lead of the 470uF goes to +5V and the negative lead goes to the GND (0V).

The negative terminal is normally marked with a long stripe along the side.

Not to alarm you but if you get it the wrong way round they can explode or catch fire. But sometimes the just give a little squeak or puff. Either way they do not survive.

In my experience, if they are rated for a high voltage, they can, but they still don't work properly. Just in case wear glasses when you power up the first time.

Thank you.

Have a nice day.

Hello again.

Cant find capacitor for 5v. Is it ok to use larger?

For both 0.1 and 470 uf