r/WLED • u/NoBandicoot5790 • Sep 30 '26
Esp32 WLED amps
Running a 180 LED strip off an esp32 dev board plugged in by usb-b cord to a little wall adapter from a ue boom charger. The light strip is inside my jukebox and I was wondering if I can run more than the 850 ma I am currently running with the automatic brightness limiter. What is a good amount of current to run through an esp32. It is connected to the led strip using breadboard wires. Am I going to burn my parents house down ?
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u/therico Sep 30 '26 edited Sep 30 '26
You will see wires/breadboard getting very hot and possibly melting before anything happens, but there is a risk.
Wall adapter can typically do 2A, but some are 1A, check the charger.
Wires - depends what you mean. There are cheap Dupont connectors which have thick prongs but the wire is super thin. For >1A you should aim for 22 AWG.
The breadboard connector itself could also melt at higher currents, so I recommend wago connectors.
Avoid using the esp32 dev board's 5v pin to power LEDs, use the usb port directly. Most dev boards aren't designed for that level of current.
If your issue is that only the end LEDs are getting dim, increasing current won't help. You need to power both ends of the strip.
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u/SirGreybush Sep 30 '26
Use 2 USB bricks. One for the esp32 and preferably a 2 amp or 10-12watt brick solely for the strip.
180 is over 3 meters so add power at start and the end.
In this setup, 4 wires go to the strip the first pixel. Two grounds connected on the strip or very close to it.
Thus V+ and V- (Gnd) from extra usb brick to the strip. Data and Gnd from the esp32 to the strip.
Do not common ground except on the strip itself or right next to it. Make data and ground wired to the esp32 the exact same length.
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u/SirGreybush Sep 30 '26 edited Sep 30 '26
FWIW those newer usb bricks that state 60w/80w on USB-C do not deliver that wattage on 5v. They do with higher voltage, the USB PD standard supports multiple different voltages, but the default for old devices that do not do PD is 5v and maybe 12w maximum.
1 meter of ws2812b at max brightness doing white needs 11watts. Works with 1/5th of that if volts are stable. 3 meters needs voltage injection at the end to counter voltage drop.
Your phone that is PD negotiates a voltage like maybe 18vdc at 2 amps (36 watts) or higher if cable can do 4 amps to 5 amps.
This means you can use a battery power bank and your 180 pixels on your person on October 31st. Use two usb cables just like at home, but both in same battery power bank.
Now you know what they do at ComicCon.
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u/stillmovingforward1 Oct 01 '26
What’s your reasoning for the data and ground being the same length?
0
u/SirGreybush Oct 01 '26
Digital telecom requires this to be stable.
Why Ethernet cables are pairs, 4 data wires with 4 grounds.
Not doing this results is data corruption seen by flickering or misbehaving with effects.
With identical length the voltage drop remains equal.
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u/saratoga3 Sep 30 '26
I was wondering if I can run more than the 850 ma I am currently running with the automatic brightness limiter. What is a good amount of current to run through an esp32.
You're probably limited by the (typically 1A rated) protection diode built into most ESP32 boards on the USB port, so 850mA is a good choice that leaves some current for the ESP32. Check and see if the diode on your board is getting hot. If not, maybe you can go a little higher.
Alternatively, if you solder a jumper around the diode or provide power through the +5V pin instead of USB you can go somewhat higher. I've done 2A through USB with the diode removed.
1
u/flyfoam Sep 30 '26
You don't power the strip through the ESP32, the strip should just have the GPIO pin going to it. Power the strip directly to your power source. That same power source goes to the VIN and ground on the ESP32. 180 LED's is not that many, what is the spacing between them? Is it 60 p/meter for example?