Simple LED Strip, I don't know if I am doing it right

Other Hardware 3rd Party Boards
1

I bought a Wemos D1 mini and I want to make an LED lamp that is controlled through WiFi, but I have no experience with electronics, and so I don't know if my lamp will fry after a day of usage.

The board says that it has Operating Voltage: 3.3V but I am connecting it in a 5V charger, it also has a 5V regulator that I have connected the LED strip, I have a feeling that I am doing it wrong.

Basically this is what I have done:

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Excuse my ignorance, I would really appreciate it if someone could help me, thanks. This is intended to be a gift and I don't want it to fry.

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It may not be that far off. Post a schematic, not a frizzy thing and include links to each hardware device. Hand drawn is fine. I would suggest not powering it up, you have a 3V3 micro connected to a 5V device. I do not know if the 5V device will send a signal back and if it can use a 3V3 signal. Your device as described can define many different devices, and this is a hardware dependent design.

3

We need the specifications of your LED ring, but I am going to say, probably not going to work.

The 5V pin on the Wemos is connected to the 5V input through a diode that is rated at one Amp. That many LEDs will draw a lot more than 1 Amp, and you aren't going to get it from a micro USB phone charger.

4

A 24-led ring could require up to about 1.3~1.4A, plus you need another 80mA for the Wemos, so a 1.5A, 5V PSU would be better. One with a barrel connector would be more robust and allow you to wire the PSU directly to the ring to avoid all that current going thru the Wemos' little PCB, which wasn't designed for that sort of thing. You can take a second pair of wires from the ring back to the Wemos' 5V & GND pins to power it.

There may be another problem. The data signal from the Wemos' pins are only 3.3V and the LEDs require a 5V signal in theory. Some work ok with a 3.3V signal and others don't. Only way to find out is to try it. If it doesn't work, you need a logic-level shifter to boost the 3.3V data signal up to 5V. But don't buy the 4-channel logic-level shifter modules commonly available on eBay etc. They are designed for use with i2c data, which is a slower rate than used by addressable LEDs. Instead, use a 74ch14 or 74hct14 chip.

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Or 74xx04, no need for the Schmitt-trigger quite a few other 7400 series would work as well, try what you have.

Definitely ! it might be able to take it, but the ledstrip need 5v, and no diode in between.

No probably not, they are usually rated at half an Amp, though there are so many varieties and some provide quite a lot of power.

The other things is the program... That it is not working could also be software related.

6

There is a diode rated at 1A from the USB port to the 5V pin.

I have driven WS2812 LEDs, both 5V and 12V with the data pin from a Wemos D1 Mini. It always worked, but the first LED has to be close to the processor. When my display is 10M from the processor, I use a sacrificial LED at the processor to act like a data level shifter.

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