I know you are not supposed to do this, but how much power can I draw through the ESP board and make available to the LEDs without popping it?
So the idea, plug a 2.4 amp USB into the board and then power some WS2812B direct from the 5v out pin on the board. I suppose, in theory, I could put as many LEDs behind it so long as I set the max power low enough. What would be the max power draw I should set in WLED to stop it burning out?
The goal is to make as simple and compact a setup as possible so that it could be embedded into a 3d printed object.
The other thought would be to use a small breadboard with a USB socket and power both the ESP and the LEDs from it instead, but that is more fiddling
The whole concept of “powering LEDs from the ESP board” is a red herring (IMHO).
Power for your LEDs comes from whatever wires connect to the V+ and Gnd pins on the LEDs.
Those wires eventually go back to some 5V power source, either a separate supply, a USB port, battery, etc.
What causes issues are all the little connections in between. The copper traces of the ESP board were likely never designed to handle any appreciable power, as the board itself usually needs < 1A.
In effect you’re trying to use that ESP board as a power distribution bus, something the traces were never designed for. The data section could care less how much power you’re passing to your LEDs (not 100% true, but I’m simplifying) and will blissfully generate a data stream as long as it gets minimal power it needs.
So when you’re designing this:
Your power supply should provide power to your LEDs with appropriate wiring.
Data supply should provide data to your LEDs with appropriate wiring.
Appropriate wiring for power is not the same as that for data and vice versa.
I know this is old but thought I would update with what I did.
In the end I got some PCBs drawn up and made at PCBWAY as a trial. I set up a trace from the wrong pin (D2 instead of D4) on the ESP8266 but it was easy to get around, and I ended up with this:
I have left spaces for a USB-C and microUSB socket to power the LEDs and the ESPboard.
This is just the Mk1 version, cost me £5-6 (along with the $5 intro offer) to get 10 boards, and even if they are not quite right, they are useable and a good learning experience.
A couple of things I have taken away from this first try:
Make allowances for plugging in the USB into the ESP board i.e. put the socket at the edge so you have the height to plug into it to do the initial programming. Also, look for some taller stand-offs or pack out the board when soldering or you wont get it flat.
Check and recheck the silkscreen information you are putting on the board, as you can see from this board I swapped the +5V and GND on the top and bottom pins, not a problem if you remember, but a stupid error.
Recheck that you are using the correct pins prior to sending the board off for manufacturer.
The breakout connections for all the pins will mean I can use the board for things other than WLED once I get the Mk2 sorted out.
My plan for the next on is to have traces for a PIR and switch once I get my head around how to add them to WLED. I would like to add a microphone too but that will have to wait for the ESP32 version and so far they seem to come with different widths so will need to be sure of which ones I get before making a new board. Not sure I will add the USB sockets to the board next time, instead I will probably just leave the pins to be connected to to supply power to everything, which will mean I can make it smaller.
The software I used was EasyEDA.
I have very little experience in electronics and none in making circuit boards and found the job doable.
