Is it possible to light up 30+ leds from the arduino board without using external power source, so im saying how many leds can 5V light up?
On average LED needs 20 mA, arduino powered via USB may supply 500 mA. Using external power source be cautious not to overheat voltage regulator IC, located near Vin connector 2.1 mm.
Magician:
On average LED needs 20 mA
LEDs do not need 20mA. That's the maximum most 5mm leds can take. But they will light with less. The more current, the brighter they shine. Some modern, high brightness leds are acceptably bright with much less. I have some which are quite useable with only 1mA.
So the answer to your question is "it depends". It depends how modern and efficient the leds are and how bright you need them. This determines the current needed. As Magician said, with usb power, you can draw up to 500mA, but the Arduino itself will need around 50~70mA, and you may have other components connected that will use current too. But if your leds work ok with only 1mA, you can have hundreds. If you need maximum brightness, then even 20 leds might overload the usb power.
You can set the current used by each led by choosing the value of the series resistor. You must always use series resistors, without them the led or Arduino could be damaged. The higher the value of the series resistor, the lower the current. Do you have a multimeter to measure the current? Every Arduino user needs a multimeter, and they are very useful and not expensive.
Paul
kevinnths:
Is it possible to light up 30+ leds from the arduino board without using external power source?
No, the Arduino contains no internal power source, so it always requires an external power source.
Your question is therefore meaningless. What you need to do is explain just what you really mean. How do you propose to power it, how would you like to connect the LEDs and what is your purpose?
If you want to control 'm using your arduino, you should keep in mind that each arduino pin can... handle 40mA max, but... the maximum amount for the complete controller is 200mA.
This Neopixel-shield can run without external power source, only with 5V from arduino UNO.
So you can put 40 leds RGB WS2812b
This test was made with arduino Due and Neopixel-Shield + spectrum analyzer from sparkfun
good day!
how to program an rgb strip to light up? i am a beginner in electronics, but not in programming. also i need to know the technical details between lighting up the strip from the arduino or as a "standalone" (if i understand correctly that means the strip is detached from the arduino and runs on some program "burned" into a "microcontroller". do i understand well? i appreciate your attention. thank you
TFTLCDCyg:
This Neopixel-shield can run without external power source, only with 5V from Arduino UNO.
No, actually, it is powered from the USB port.
Which incidentally, generally has a lot more "grunt" then the regulator on board the UNO.
yoni11:
good day!
how to program an rgb strip to light up?
Hello and welcome.
Please start your own topic for a new quesiton. Don't try to hijack someone else's topic (even if they seem to have abandoned it, like in this case).
Paul
kevinnths:
Is it possible to light up 30+ leds from the arduino board without using external power source, so im saying how many leds can 5V light up?
74HC595
or
TLC5940
or
MAX7219
pick one kind of chip and just daisy chain them (so many leds per chip... are they single color, bi-color or rgb?).. (are they 2pin, 3pin or 4pin?) - you can control tons of leds.. just how you go about is the thing
i'm sure there is other chips out there, but those seem to be the most i hear about..