ws2812b power with 3.3V

i use a ws2812b ledstrip and power it with 5V..but the data signal comes from an esp32 (3.3v)..it works fine.
but i would like to know if i can also power the ws2812b ledstrip with 3.3V (its more convenient for my battery powered project). will it work and be safe long term? (datasheet says 3.5-5.3V power supply)

Probably not. The red LEDs will work ok. The green will probably also work, but the blue probably will not work. As the batteries discharge and the voltage drops, soon the green will also stop working.

What batteries are you using?

You must not power the strip from the 3.3V regulator output of the esp32 board, you might burn it, or it will shut down because of overheating.

color is not super important for me.. also, i dont plan to blink more than 1 maybe 2 leds at the same time..
i use 18650 batteries..

no, i am not powering the ledstrip from the esp32, i have an external regulator that i want to power both esp32 (straight to 3.3V pin) and the ledstrip..
not powering the ledstrip FROM esp32..

uzer123:
i use a ws2812b ledstrip and power it with 5V..but the data signal comes from an esp32 (3.3v)..it works fine.
but i would like to know if i can also power the ws2812b ledstrip with 3.3V (its more convenient for my battery powered project). will it work and be safe long term? (datasheet says 3.5-5.3V power supply)

Depends how lucky you feel and how reliable you want the application.

The controller is outside spec already at 3.3V, so maybe the whole thing will stop working at some point.

The controller at the end of the strip would be even further outside spec.

Try it and see.

You could try powering the strip direct from the batteries, no regulator, and the esp powered from the batteries to its 5V/Vin pin, using its on-board regulator. If it works ok with the battery fully charged (~4.2V) it should work until the blue LEDs stop working.

hm...thats a good partial solution..BUT the ledstrip is crucial for my project, so i have to be sure that the ledstrip is working as long as esp32 works (btw i use dont prefer 5V pin because the onboard regulator is very hungry..
i plan to use mcp1700 which is using much lower power.
So, i guess i have to try and see what 3.3V can do..

blue is supposed to need lower voltage than the other?

Red needs lowest voltage, blue needs highest.

Mcp1700/1702 is a good choice.

What esp32 board are you using and what model of "hungry" regulator is onboard? I would like to know that so I don't buy one by accident. I use Wemos mini (esp8266), which has a good low dropout regulator.

For reliable operation of the LEDs, you should consider a 5V buck converter. But then you may also need a level shifter for the data signal. Use 74hc14 or 74hct14 for this, not one of those i2c level shifter modules.

The controller is outside spec already at 3.3V, so maybe the whole thing will stop working at some point.

why? esp32 can work with 3.3V so you bypass onboard regulator also (as far as i know)

this is what i use.

[qote] you should consider a 5V buck converter. But then you may also need a level shifter for the data signal. [/quote]
do you suggest any low power 5V buck converter? Level shifter looks, is not in need..
i have used two different projects and ledstrip works fine without one..(i just added a resistor to data pin)

uzer123:
do you suggest any low power 5V buck converter? Level shifter looks, is not in need…

I do not have a recommendation for you, sorry. Maybe you will not need a level converter, if you are lucky. Let us know how it works out.

just an update:
WS2812 ledstrip CAN work with 3.3V supply (lipo in 3.3V LDO), and also esp32 can control it successfully with 3.3V logic.
I see that according to the datasheet here https://cdn-shop.adafruit.com/datasheets/WS2812B.pdf it works fine:
VDD: +3.5~+5.3
Input voltage VI: -0.5~VDD+0.5 V
So, my supply of 3.3 is within specs..
Also Vih and Vil are 0.7Vdd and 0.3Vdd, so it depends from the Vinput,
so if i use 3.3V power supply AND 3.3V logic of esp32, its better than 5V power supply and 3.3V logic.
In any case, every combination looks to work..

uzer123:
just an update:
WS2812 ledstrip CAN work with 3.3V supply (lipo in 3.3V LDO), and also esp32 can control it successfully with 3.3V logic.
I see that according to the datasheet here https://cdn-shop.adafruit.com/datasheets/WS2812B.pdf it works fine:
VDD: +3.5~+5.3
Input voltage VI: -0.5~VDD+0.5 V
So, my supply of 3.3 is within specs..
Also Vih and Vil are 0.7Vdd and 0.3Vdd, so it depends from the Vinput,
so if i use 3.3V power supply AND 3.3V logic of esp32, its better than 5V power supply and 3.3V logic.
In any case, every combination looks to work..

Um - 3.3v is not between 3.5v and 5.3v... Am I missing something there?
My experience with the LED strips has been that as long as the control signal logic levels are high enough to meet the Vin(high) spec, you don't need a level shifter;
Powering the WS2812B with voltages on the low end of that range is no fun, though; the issue is voltage drop along the length of the string - you put power in at one end (or, for longer strings both ends, and at point(s) in the middle if you have to) but the strip itself has a non-zero resistance, so the voltage droops farther from where you are injecting power. The 3.5v~5.3v figure is - I suspect - intended to help people plan their power distribution scheme in longer strings, which can be non-trivial.

Use the incoming power from the wallwart, use a switching regulator to step it down to 5V for the led strip, use a mcp1700 to step down the 5V to make 3.3v and feed to the ESP32.

I found, from my solar powered weather project, using the ESP32's on board 3.3V regulator is a power waster over bypassing the onboard regulator and using a mcp1700, instead, to make 3.3V for the ESP32.

DrAzzy:
Um - 3.3v is not between 3.5v and 5.3v... Am I missing something there?
My experience with the LED strips has been that as long as the control signal logic levels are high enough to meet the Vin(high) spec, you don't need a level shifter;
Powering the WS2812B with voltages on the low end of that range is no fun, though; the issue is voltage drop along the length of the string - you put power in at one end (or, for longer strings both ends, and at point(s) in the middle if you have to) but the strip itself has a non-zero resistance, so the voltage droops farther from where you are injecting power. The 3.5v~5.3v figure is - I suspect - intended to help people plan their power distribution scheme in longer strings, which can be non-trivial.

To my understanding, Vdd should be between 3.5 and 5.3V, but the Input Voltage can be 0.5 lower than Vdd, so my lowest voltage can be 3.0V.
My ledstrip works fine for a long time till now with 3.3V power and 3.3V signal coming from esp32, but as you say maybe it has to do with the injecting power point. In my project, i use only 1-2 leds at a time and i never light up all the ledstrip at once.
My scenario is fine, but if i wanting a full bright ledstrip with 24/7 lighting maybe it had issues..
At least i know for sure (and for anyone interested) that 3.3V supply with 3.3V logic works, but maybe not in all cases...

Use the incoming power from the wallwart, use a switching regulator to step it down to 5V for the led strip, use a mcp1700 to step down the 5V to make 3.3v and feed to the ESP32.

I found, from my solar powered weather project, using the ESP32's on board 3.3V regulator is a power waster over bypassing the onboard regulator and using a mcp1700, instead, to make 3.3V for the ESP32.

Yes, that's a scenario that works for sure, and indeed mcp1700 is a much better choice than crappy onboard AMS1117. The problem is that in my case i power from a lipo, so the ledstrip needs a boost converter for 5V, but it works as it is anyway..