Help with WS2812b strip: Mood sensor project

Hello all,

Im currently doing a project related to environmental moods. The basic is that, I gathered several sensors (sound, PIR, DHT11) and the changes in the environment will be detected by these sensors and displayed on a sign (45cm H & 150cm W) that im planing to light using WS2812b strips and controlled using an Arduino Nano. My display is a DIY I did using cardboards shaped into large block letters. I have few questions and suggestions.

I don't want to use the WS2812b strip right away on the sign. I need the individual LEDs on the strips to be placed further away from each other. So i have to cut each LED unit and connect somehow. So, i estimate around 150 such LED units.

  • Is it possible for me to solder these using thin copper wires? and if it is so, i would like to know the gauge size.

  • If i solder each unit this way, will there be instabilities in the colours and the illumination of the LEDs?

  • Can i solder all the 150 units and control using a single Arduino pin? (now, due to the extended distance. 150m long)

I have completed the code and tried using a 60LED/m WS2812b strip. Now i need to expand this to my sign. I highly appreciate any answers and suggestions.

You might have need to use these, ALITOVE WS2812B WS2811 SPI Signal Amplifier Repeater, or not.

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Not so "thin". 150 LEDs might draw 8 Amps at full white, so the power wires (5 V and ground) must be suitable to carry this through the chain. It is probably appropriate to have separate power wires (5 V and ground) from the supply to each major section of your display however wherever the signal goes from one LED to the next, it must always be accompanied by a ground wire rated for the full current to those sections. All such wires must be kept together as a pair (or triplet including the data wire) as they travel.

Not if those conditions are fulfilled.

As long as the distance of the data line between each LED and the next is not excessive. Each LED acts as a "data repeater" so you generally do not need one (74HC14) unless that distance approaches a metre or so.

Thank you for the amazing reply. This is actually my first time trying to do this, so I still have a lot to get clarified here. So, according to what you have mentioned here, i will go with the option to use separate power wires (GND and 5V) and provide power separately to the main sections of the whole setup. Meaning, i have to connect the two copper slots on either sides to give power accordingly. Now the data slot is in the middle. Each unit ( Individual LED unit) will be located around 3cm away from each other. So, now i can connect all the 150 units using a continuous copper wire (since the same data has to be passed to all the units). From what you have said, do i now, have to pair each of this data slot with a GND?

Not sure what you mean by "continuous". The data connects from the "Data out" pin of each LED to the "Data In" pin of the next one in the chain. It is not otherwise continuous.

The data passing from one LED to the next has already had the data corresponding to the first LED, removed by that first LED, so it is not quite the "same" data. :grin:

Wherever the data connects from the "Data out" pin of each LED to the "Data In" pin of the next one in the chain, it must be accompanied by a ground wire connecting from the first LED to the second, and preferably also a 5 V wire. Since these wires may share some of the general power draw of the strip from one part to another, they should be sized appropriately.

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Thank you. I got it working :slight_smile:

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