Hello everyone! First project, First topic.
I'm Building a macro keyboard as a fun project using a Pro Micro ATmega32U as controller, It has USB-c connector.
I was wondering if I can power a led strip directly from the pro micro, maybe adding some resistence, or if i should use another model with usb-a.
I'm super noob on Arduino sorry if my topic doesn't make sense
I do not think the type of usb connector will make a difference. The maximum current will still be 500mA.
Yes, you can power an led strip this way. A very, very short strip!
For example if the strip contains ws2812 LEDs, the strip can have maximum of about 8 LEDs.
Thank you so much for your answer!
And no further component Will be needed to connect the led strip to the pro micro?
I cannot answer that. You need to provide details of the strip.
how much consume the strip depends from current color (if RGB strip) and intensity(brightness/duty cycle)
You are right, my mistake. However, the LED strip in question is a leftover piece from one I bought months ago and was the excess part that didn't go behind my TV. I don't know the specifications of this LED strip, beside being RGB, and can't figure out how to find them on the strip itself. I would be open to purchasing a specific strip if you could give me some advice.
How many contacts does it have each end and how are they labelled ?
It has 4 pins:
After some googling I'm back, and I want to update everyone with the solution:
You can power an LED strip with a Pro Micro.
First you have to connect the VCC to the +5V pin, then connect pins 6, 9, 10 each through a 220Ω resistor to the base of three NPN transistors. Next, connect the emitters of the transistors to GND and the collectors to the respective R, G, B pins of the strip.
Hope this helps
The caveats expressed by others earlier still apply. 500 mA, MAX, on a USB connector, and you'll need to figure out what the current-per-LED is to ensure you don't exceed that maximum.
Far, far better to use an external power source, if you have one available.
Thank you for the advice! My project is a macro keypad with RGB lighting, and I'm trying to make it as similar as possible to industrially produced models, which typically operate with just one USB cable.
I'm aware of the current limitations of the USB port. As PaulRB mentioned, I should use a maximum of 8 LEDs to avoid exceeding 500 mA. I followed this advice and hope to avoid any damage by keeping everything within safe limits. I'm not sure how to calculate the current per LED exactly, but I'm trying to ensure my project is safe.
I really appreciate your concerns and suggestions!