Multiple LEDs on Arduino pin 13

Hello,

My idea was to create a simple LED light that I could control with my phone (android) using Bluetooth. I am using the BT module HC-06 so therefor using 3.3v and a voltage divider for the TX and RX communication. ATM my LEDs (6 of them) are running on the same 13 pin from the Arduino.

My question/problem is can the Arduino correctly power those 6 LEDs from the same pin without any further complications or I should use individual pins for each of the LEDs?

thank you !

Hi, and welcome to the forum.

RobotL17:
My idea was to create a simple LED light that I could control with my phone (android) using Bluetooth. I am using the BT module HC-06 so therefor using 3.3v and a voltage divider for the TX and RX communication. ATM my LEDs (6 of them) are running on the same 13 pin from the Arduino.

My question/problem is can the Arduino correctly power those 6 LEDs from the same pin without any further complications or I should use individual pins for each of the LEDs?

You didn’t say which Arduino. Some Arduinos (e.g. a Nano) have an onboard LED (uses 6mA) directly connected to pin13. Other Arduinos (Uno/Mega) use a buffer chip to power the onboard LED. Some flash the LED on pin13 during bootup. Best to avoid pin13.

Pin (LED) current should be kept <= 20mA per pin, with a total of <200mA for the whole chip.
Best to use 6 pins for 6 LEDs with 6 current limiting resistors.
Assuming white LEDs with a Vf (working voltage) of ~3.3volt, CL resistors can be (5v-3.3v)/0.02=85ohm (minimum).
I would use a 100ohm current limiting resistor per LED.
Leo…

My question/problem is can the Arduino correctly power those 6 LEDs from the same pin without any further complications

No. If you only want to use one pin then use six WS2812b LEDs. While you are not powering the LEDs from the pin you are controlling them.

You could use a MOSFET to control current in the LEDs while still using only one pin.