Hello,

This is my first post here, so hello!

I'm working on an led sign. I have over 200 leds connected in series pairs with a 150Ω resistor. I'm using an Arduino Microcontroller to output to 3 arrays of leds. I'm using an N type mosfet(IRF 510) that uses the logic signal from the arduino to switch the power on and off from the second power source. I have a diagram. the sets of LEDs are representations of much bigger arrays.

The problem is when I output a logic 5+ signal to 1 array they all turn on. I want to be able to activate each of the transistors independently with the 5+ signal from the micro controller. thanks for the help!

 

Hello,

Which arduino are you using?
What program do you use?

Here is some info on arduino's:
http://www.arduino.cc/
http://opensource.wikia.com/wiki/Arduino
http://www.ladyada.net/learn/arduino/

Greetings,
Bertus

 

You have the Mosfets connected backwards. The source should connect to 0V and the drain should connect to the cathode of the lowest LED.

Your circuit does not have a common 0V and I don't know why it has two 9V batteries.

 

As audioguru has indicated, your circuit is miswired. When you turn on any one of the mosfets, the negative terminal of your battery is tied to ground and therefore all of the leds are illuminated.

hgmjr

 

Thanks got it!