Need help with extremely complicated ws2812b strips project!

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You can list the major areas where you need to make decisions.
LED strips.
Power Source.
Connecting.
Controllers.
Programming.
Of these the LED strips and power source have many options available, and making changes as the project develops is relatively easy. Connecting it all together might or might not be within your skill set, but is not a difficult skill to acquire. Remember to include any equipment (soldering station, crimping tools, etc) in your budget. The last two are where the options vary widely in terms of functionality available and the effort required to implement.

So for starting with a small test rig it doesn’t matter much what you choose - a ESP32 dev board, 1m WS2812b strip, a 5V 2A adapter, a breadboard and jumper wires is enough. You can install WLED and play with it, or modify example sketches for custom effects

Off-the-shelf controllers will be easy to implement (requiring some setup, but no programming as such) but will only provide a limited range of usable effects. Once you have determined exactly what your effects are going to be, you can look for controllers that would be suitable. I would expect that some of the simpler effects would have suitable controllers available at very low prices, but note that there is not much standardization in effect names (what exactly is the difference between meteor and icicle?) and you might have to buy a number of controllers to see what their effects actually are and whether they match what you want. It is possible that preconfigured controller/LED strip packages will meet some of your requirements.

Custom effects will be where it gets a lot more difficult.

Very simple 8-bit microcontrollers can be used for individual strips. They are very small, low power and readily available. But they have limited memory and programming is probably at either the assembly language or C level.

Arduino Nano/Pro or ESP32C3 represent one step up. Still small, more memory, (and more power), programming is in C++ and there is a range of very good libraries available.

More complex MCUs such as RP2040 can be programmed with higher-level languages, such as C++ or Python and will control multiple strips (but that means more complex interconnections). They consume more power and create more heat. Good libraries are available. These MCU (and most ESP32) will also support WLED, which provides a very comprehensive development environment, but it is very far from a beginner’s GUI.

In fact, if you can find a beginner’s GUI for effect development then that might be a better starting point, as that will suggest the most suitable hardware. I don’t know of anything that is available.

A very good place to start investigating exactly what is involved in making large LED strings work is bigclivedotcom - YouTube, especially the Christmas Tree episodes (but note that he completely skips over programming the controllers) and the reviews of cheap preconfigured strings with their own controllers.

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I’m extremely puzzled; I noticed that in terms of splitter cables their 3-pin male output doesn’t match with the WS2812B (SMD 5050) LED strips’ copper pin layout. Since each divided section for each diode is marked by a 3-pin divided line, I thought it means that it can only support 3-pin cable connections. I might be wrong, but are there splitter cables with the appropriate 3-pin male connector parts to match each copper dividends on such LED strips? Also I’m confused as to how to connect a Pi Pico, a ESP32 or similar controller module and battery pack/12000mAh powerbank to a max of 4 led strips (lengths could vary but at least 92cm) connected via splitter cables since there’s only a couple of input/output ports on those controller modules and without matching/not enough connection ports it would be extremely complicated to figure out how to set about their connections layout. Any tips?

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What splitter cables are you referring to? The three tabs on the WS2812B LED strip are +5V, Gnd and Signal. +5V and Gnd are from the power supply for the LEDs, Signal is from the MCU GPIO. Make sure the MCU ground and the LED power supply ground are connected.

If you have four LED strips that you want to control separately then you would use 4 GPIO ports on the MCU. The devices you have mentioned all have more than 4 GPIO ports available. Each of the LED strips uses the same 5V and Gnd from the LED power supply.

If you just want to connect multiple strings together to make one long string then you only need one GPIO port for the whole string. Depending on the length, it might be worthwhile to connect 5V and Gnd from the LED power supply at multiple points on the long string.

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Hi @Darkmaster288884

ws2812b LEDs are addressable, meaning that each LED on the strip can be assigned a brightness/colour rather than the entire strip being the same. I would recommend using 4 separate GPIOs for controlling the 4 strips in a similar fashion to the below photo.

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To answer to those who didn’t understand my queries, here’s a draft of how each components were believed to be hooked up to and connected. This is just a rough idea as to centralise each system connecting a max of 4 LED strips per microcontroller (Pico Pi, ESP32 or any other types), with the power source to either be a battery pack (connected to a voltage booster?) or a powerbank (12,000mAh or more) connected thru a USB powered KeepAlive. It took me a lot of brainstorming and research to realise that the splitter cables’ pin connectors won’t fit on the tabs of each LED strips, and that JST SM 3-pin cables were what connects between separate LED strips. I still am not sure if there’s other components that you can all suggest I should add to prevent any issues such as voltage inconsistency, wire strains, physical wear and tear, flexibility, etc. Also, if all the animation presets were arranged in a timeline (like a movie maker style format) thru the microcontroller, would it be possible to have all LEDs turn on (and off) at the same time using a master switch in an WLED supported app or remote? Let me know what your thoughts are and any useful suggestions.

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One more thing to keep in mind will be heat. The more “on” the led is the hotter it gets. One of my long term projects has 1024 LEDs in a 32/32 grid. this then sits in a 3D printer diffuser grid (to give a sort of square pixel bleed affect). then all that is behind some tinted acrylic for make it look black when not on. So my design will tend to want to trap the heat, so keep that in mind.
When showing bight colors my flir shows about 60-65 deg. C with no heat sink.

With power, Im not sure of any “rule of thumb” but you should add power at more then one point. e.g. at each point where you join strips/segments together, add a power cable back to the power source. Yes its more wire, but should address any issue.

If you are going to solder wires to the strips, you may be tempted to cut down the middle of the pad cut point… and you can make it work, but it wont leave much to solder onto. As such I would suggest you leave the entire pad behind and sacrife an led (to get the full pad) It will give a much bigger pad to solder to. Also keep in mind you will want to play and practice a bit with it, as most strips will have a coating over the pads that will need to be cleaned off in order to solder to.

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What are you referring to as the pad? All I see are just the power supply, the microcontrollers (pi pico, esp32 or any other related types), the JMT SM 3-pin wires and the LED strips themselves. Surely they have no need for a power booster in order to meet the energy input/output thresholds? Also to address potential issues regarding wire strains that soldering could not always resolve and overheating would there be cooling equipment/accessories that keeps heat levels at reduced amounts? And to question the need for splitter cables instead of JMT SM 3-pin wire connectors, which is the better choice? How can they be soldered at the right terminals in which a ESP32/pi pico/seeed studio xiao has numerous of? How can more than one microcontroller be activated/deactivated altogether at the same time? Is there no master switch in an app or remote that does the job?

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The pad I am talking about is on the LED stripe. at some point you will/may need to cut the stripe to make it shorter/ or join together.
In the image you can see the 3 pads with a “cut line” Depending on what strips you buy, those pads may not be big enough if you cut on the line, if you want to solder wires to it.

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If I take your diagram literally then you are providing power to the LED strip from the power supply (blue) via the microcontroller (yellow). That won’t work. The power for the LED strips must come direct from the power supply. The USB power is only for the MCU.

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The connections I have added are a minimum - experience with the final version might indicate that additional power feeds for the LEDs are required, as mentioned above.

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Thanks for clarifying. If the JST SM cables were to have a USB-male port then I can certainly connect additional cables to have direct access to the power source (be it a high-capacity powerbank or battery pack + possibly voltage buck/power booster). However since those cables have nowhere to be soldered/connected to due to the power source having no exposed circuit board (and thus no contact tabs) and the cables themselves having no USB type A ends, I’m struggling to understand as to how such strips can be connected to both the microcontrollers AND the power source.

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If your power source only has USB outputs then it’s probably the wrong power source for this application. Each USB port is typically limited to 500mA, but each of your strips will require more than this. Even if you have a power source with ports that can supply more than 500mA you will have to ensure that you use a USB cable that can handle the higher current - many standard USB cables can’t. Without knowing what your power supply is it is difficult to be precise, but the important rules are:

  • Do not use the 5V link form the MCU to power the LEDs.
  • Do not power the MCU from a USB connection that is shared with the LEDs. The actual power source (the battery) might be shared, but the USB supply from that battery cannot.

If you are doing your wiring based on what connections you can make using the materials you have, then you doing it the wrong way around. You need to work out what the wiring should be, then choose the components that enable you to build it as required.

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I’m really confused here. If battery packs or even powerbanks won’t work at all simply because they share connections to the MCU, or that it’s not worth connecting the MCU to the LEDs, then what exactly would work??? Are you thinking that the only possible way is to connect it to a massive power source such as a wall socket/power outlet and regardless what I do it will only compromise the functionality and condition of the LEDs. I cannot come up with any other components or settings that can deliver the results without risking a malfunction as you adviced, and now I have no idea what’s more safer and works the way the video shows. If you can at least point me in the direction of which cables to use, which PORTABLE power source I can rely on, which other type of LED strips has little to no risks of malfunctioning in such an arranged setup AND be addressable like ws2812b 5050 strips, it would save me a lot of mental homework and brainstorming over trying the come up with something rather than figure it out through clues and experimenting with risks and mishaps. Perhaps I ought to also add my level as a beginner just to indicate that complicated brainstorming comes at the expense of endless research that is filled with different various ‘solutions’ and ‘experiences’.

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Nobody suggested that. Using a single battery pack or powerbank for powering both the MCU and the LEDS is not a problem. But it’s not the battery pack that is driving either the LEDs or the MCU - it’s the adapter that converts the battery voltage (probably between 6.4V and 8V) to 5V. Sharing the battery pack is not a problem. That battery pack may have a 5V adapter built in (or it may have several 5V adapters built in). It is sharing that adapter between the MCU power and the LED power that can create a problem. If the MCU and the LED share the same source then changes in the load that occur as the brightness changes will affect the supply to the MCU. There is also a lot of noise associated with driving the LEDs. The voltage variation and the noise will affect the MCU, creating odd problems such as random rebooting. The best arrangement is a battery pack with a very large 5V adapter for supplying the LED power and a much smaller 5v (or 3.3V, if applicable) adapter for supplying the MCU power. If that is built into one unit that’s optimum. If your MCU is a 3.3V chip then a good arrangement is a very large 5V adapter built into the battery pack supplying the LED power and also supplying a 3.3V adapter for the MCU - the 3.3V adapter effectively isolates the MCU power from the LED power (and a 3.3V chip will usually be OK for controlling the LEDs). Another option is a large battery with a 5V adapter for the LED power and a much smaller battery with a 5V (or 3.3V, if applicable) adapter for the MCU, but two batteries is obviously inconvenient. A useful alternative, although harder to find in the marketplace, is a battery pack with a large (or multiple) 5V adapter for the LED power and a separate connection direct to the battery, which then drives the adapter that is built into most MCU development boards. There are many ways to do it, but plugging both the MCU and the LEDs into the same 5V source is inviting problems.

The reason that you can’t connect the LED power to the MCU 5V is that the design of the MCU development board, and the whole power chain back through the USB cable, means that the components are not able to safely handle the current that the LEDs will draw. At best you will get a significant voltage drop at the LED end, and at worst you will burn out a PCB trace or a wire or connector somewhere.

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Are you suggesting that i could use a large capacity power source (e.g 20k mAh powerbank or higher capacity battery pack) just solely for the LED strips, and a separate lesser capacity power source (i.e 5000mAh powerbank or mid-range battery packs) solely for the MCU itself? The question is, how can the MCU transmit any data without sharing the same wire connections as the LED strips? Perhaps a BLE module or other wireless transmission methods could address that?

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When looking at power supplies, you will need to know two key “currents”.

  1. What is the stored power, this is normally rated as Xma hours. or mAh as per your example. This is more a measure of how much power can be stored in the battery bank.

  2. Max current supply. This will tell you the max/peek current that the power bank can suppy.

e.g. You have have a 20,000 mA/h = 20 Amp/Hr
so if you are drawing 1 Amp, you will get 20 Hours of power.
If you are drawing 2 Amps, then you will get about 10 Hours of power.
BUT if the max power current it can supply is less then you need then it wont run what you need it to run.

the wire you use (as stated above) needs to be able to carry the current you leds are using. You can split this by running more then one power cable, but the wire still needs to carry that current. e.g. On my 1024 LED project if I run peek brightness and have white, then those supplied wires on the JST connecters get hot (or warm to the touch), so running more then one set back to my power supply spreads the load and the run cooler.

Please note: the key point everyone is trying to make is…

You need to know the power needs of the LED’s (and controllers) first. Once you know the power you can then find cables capable of supplying that power (without getting hot) If those cables are too big, then you need to split of multiple smaller ones (hence my earlier comment about running power to each segment).
and when you know the peek power needs, you can select the power supply that can supply that, and/or spread over more then one.
Keeping in mind that once you know the peek power (plus a buffer) and the run time, you know have the specs. for the power supply.

e.g. Lets say you have 300 LEDs. Lets go with 50mA per LED (this is note well documented) then the power needed will be 300 * 50mA = 15000 mA (15 Amps).
If you need that to run for 5 mins; then…
5/60 = 0.0833 hrs, so 15 * 0.0833 = 1.25 Amp/Hrs
We can check this Math : 12 * 1.25 = 15 Amp/Hrs (i.e. if we run it for 1 hrs which is 12 * 5mins)
So now you would know (for this example) that you need a minimum 1.25 Amp/Hr power supply that can supply continuous peek current of 15 Amps, and that will run for 5mins then be flat.

So note: the peek current supply will the be important part.

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Two battery packs (one large for the LEDs and one small for the MCU) is one option, but not the best. If you do go that way, check the requirements of the two loads very carefully - you want to end up with battery packs that will last about the same time for the two jobs. Otherwise you will be carrying more weight than is necessary.

The MCU will control the LED strips with the signal connection, which is independent of the power connect - with a single exception: there must be a common ground between the power and the logic. The diagram I posted above has a common ground in the PS (blue) that is connected to the MCU (yellow) in the USB cable (white) and the LEDS in the individual GND (green) connections. Other arrangements (such as separate battery packs) may require special ground connections. That’s one reason that separate batteries is not the best option.

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Darkmaster288884
Please keep in mind, that people here giving advice and guidance will have come from actually doing things like this, then working the problems that come up.

Some of us will activity run tests to confirm things.
I really cant stress enough, that given your background and experience and this project, that you start with a basic setup and test and take it from there.
e.g. Get some LEDs and controller, write/install what ever you thing will do the job and test it. I would not assume that going direct to a final build will work; It may work, but it may also have issues that you will then need to retro fix.

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Hi All
I will just butt in here for a moment.
No one seems to have twigged to this rating of the usual “Power Bank” which seems to be the favoured option.
That rating in mA/hrs is AT THE BATTERY (3.7V) and has to be derated at 5V.
For instance I have a 15000mA/hr power bank. Which states this is at the battery clearly on the case. By the time this is converted to W/hrs and consider a conversion factor this reduces to 11000mA/hr. Far less than 15000. I have verified this by the way with a resistor discharging at about 350mA and with a USB monitor device that records mA/hr. The power bank shut off at about 11000mA/hr.
You should also subtract from this any derating of the capacity caused by drawing large currents which most “power bank” will not supply anyway.
The real world can be a different place sometimes (read most times).

Do what Michael says. Work out what you NEED before worrying how you are going to SUPPLY it.
Cheers Bob

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You mentioned earlier that using one battery pack/powerbank for a set of 4 LED strips risks overheating, but now running one power source for each LED strip require special ground connections and that is something you’ve adviced against. I think if I provided the specifics on what components I plan to use maybe somehow you could give me a much simplified proposal on how I should hook them all up without missing out on any of the power requirements or disregarding functionality issues.

Strips used: 4x WS2812B (SMD 5050) strips 144LEDs/m IP67
Calculated that for each strip 43.2 Watts DC 5V requires 8640 mAh, which even a 10k mAh powerbank connected thru a USB keepalive could possibly run for a continuous min. of 5 minutes.

MCU: this is a tricky choice. Dan recommended either a Pi Pico, Seeed Studio XIAO ESP32-C3 or another ESP32 module. I’ll pick whichever is the easiest and less of a hassle to maintain, but I’m certain they have a low-power state meaning they don’t easily overheat by themselves.

Wires/cables: the big difficulty is how can I connect an MCU to the LED strips to enable data input/output so that the desired animation sequences can run as intended without using the wrong wires or having the need to connect all components centrally to both the power source, MCU and LED strips. There’s no way the MCU can run without any power but you suggested that all the other components cannot connnect to each other and that branching off wire/cable-connections can cool down the LEDs a little. I feel somehow if there is a BLE module that does not require wired connections to the MCU and perhaps a heatsink of sorts to make the process more effective it would probably decrease the pressure of the components overperforming and thus less chances of overheating.

The adapters are difficult to find because I have no directions to follow for such results and the adapters could be anything, not just cables.

Perhaps a diagram of how the power sources (and exactly how many) can power the LED strips AND MCU together and the BEST cable adapters and where theyare supposed to connect with each other without becoming a jumble of interconnected and potentially overheated mess as you predicted. Remember this is LED textiles related so every component is meant to be portable and compact yet able to deliver so-preferred results as shown in the video, that is if I’m not sure if you’ve even watched it to get an idea where I’m trying to get to with this approach.

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I’m trying to @Robert93820 but you seem to think this project is impossible (much like @Michael99645 believes it to be), when there are others who are able to pull it off and it shows. Sure I’ve researched intensively for several weeks, compiled a list of specific versions of each equipment that performs accordingly to the project’s results and even noted from various experts despite warnings from a few regarding the publicly available portable power sources to be unable to deliver the sufficient energy input/output to showcase the effects, there is a minimal Wattage/mAh threshold to meet in order to power them even for a mere 5-10 mins. And that lowering the LEDs to 75% brightness isn’t going to change that overperforming 100% white color mode (whatever its supposed to mean).

Now unfortunately, as I am on a budget, buying a demo set of LEDs and controller for testing would put a strain on spendings, and it may/may not help me determine to full-scale if it applies to more “demanding” full scale requirements as many others have seen, but if people are resilient that it still is impossible to pull off, I’m more than willing to refer them to a few links just to show it is POSSIBLE and can be done. It just comes down to thinking and brainstorming how exactly did those cases of success pull it off and made it a reality.