Control 5V relay with my BeagleBone Black GPIO


I have a 5V Relay shield to control with my BBB, i know the GPIO work with 3.3V, i see an instructable that i can shunt the leds in my relay shield and it will work, it is safe for my bbb to do that?

Modifications for Driving a 5V relay module from a 3.3V Arduino board

My relay board:

Relay Board



I took a look at both circuits.

There’s uses an opto-isolator, so shorting the LED should work.

In your case, the 1K resistor on the base will load the GPIO too much.

I used a 10K base resistor with a 100K pull down.

Basically multiply both of your values by 10 and you8 should be fine.

I would hook the LED in parallel with the relay coil.

Good Luck


Hi bill,

Thanks for your help, so i just have to replace the resistors by new ones, for Leds what is your idea to connect them to relay coil?

segunda-feira, 9 de Fevereiro de 2015 às 20:57:06 UTC, William Pretty Security escreveu:

You should be able to just the replace the resistors.

On second thought, the LED across the coil was a bad idea.

Maybe someone else has a suggestion on that one.

“No one could make a greater mistake than he who did nothing because he could do only a little.”

“All that is necessary for the triumph of evil is that good men do nothing” Edmond Burke (1729 - 1797)