Asked — Edited

Led Lights

Hello Everyone,

I was wondering if anyone knows how to wire LEDs to the EZ-B?

What kind of LEDs are compatible as far as voltage and brightness and do I also need resistors?

Please let me know when you can.

Thank you,



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LEDs are simple to add. Using the digital pins outputs 5V when on, 0V when off. Leds can be rated for 2.5V to 3V so simply pick a current value suitable and calculate the resistance needed for 2V. [V=I*R]


Also, if you are powering the LED from the EZ-B signal line, you won't need a resistor. You only need a resistor on the EZ-B if you are powering the LED from the +5 and GND. But if it is the signal line (where you can control on or off) then you don't need a resistor :D


Thanks Guys!!!

I remember seeing a tutorial on this web site on how to add them to the EZ-B.

If you know what I am talking about, please send me the link.

So if I am correct, you connect the ground to the ground and the psitive to the signal?




GND-Cathode (-) Signal-Anode (+)

Yes exactly as you have it.


Sweeeeettt!!!! Thanks!

Can I connect these in a series to one digital port or do i need to connect one LED to each digital port?

i really just want to connect two for the eyes and here are the LEDs i am planning on using:

10 mm Ultra Bright LED FW Supply: 3.5V (typical), 4V (Max) FW Current: 20mA

Let me know what you think of this LED, or if you can suggest other ones that i can use.

Thanks again for the help.

  • Chris

Connect in parallel you can probably place 10 perhaps. I use a 7.4V 910mAh LiPo which gives me roughly 220mA on a port, I think. Those will work fine.


Sounds good. I am only going to have two LEDs for now so I think I should be fine.

You have been a great help, and I really appreciate it.

I will let you now how it all works out.

Thanks again.

  • Chris

Hey orwnic82,

I heard that it is not good to wire LEDs in parallel. What do you think?


To me, I do not see why there would be any reason to believe it to be bad on an LED to be in parallel. I have seen many main stream products wired as such and have never had a problem doing it my self. Just LEDs( Light Emitting Diodes) current only flows in one direction and placing them in parallel just allows them to be set at the same voltage level but each has its own current level, as long as they are the same type each should have the same current level then too.

Just try not to mix and match LEDs of difference, use same rated and perhaps same colored.


Sounds good to me. I am going to take your advice.

I just ordered my EZ-B kit as well as the bench power supply.

Hopefully it wont take to long to come. I have other parts ready i just need to put stuff together.

Thanks again,



No prob and even if it's a bit late it is a platform worth while. I've programmed with multiple different controllers and I really believe DJ has put a lot towards making this product what it is. Not only in the sense of the EZ-B's abilities but allowing multiple different backgrounds to exercise their creativity in building and playing with electronics, both hardware and software alike.


I agree, it has a lot of potential. I have a project in mind that I have been planning for over a year.

I know a little bit of programming with VB and the software is very user friendly.

I am able to do a lot and I can't wait until I receive it and begin posting pictures.

I appreciate the help and keep doing it. It is people like you in the EZ-Robot community that allows people like me who do not know as much yet to step out with confidence and actuaully build something.

Thanks again,