ardunio gives off a 5v signal ( i might be wrong, -_-) but i want a 3.3 volt signal for LEDs. is there a way to change the signal to 3.3v? do i need to bother?
Why do you want 3.3V for an LED? The traditional way of doing this is to add a resistor. The value of the resistor depends on the amount of current you want flowing and the difference in volts between the supply and the forward voltage of the LED. Ohm's law does the rest.
Here is an example. Assuming you have 5V and a red LED which has forward voltage of 2V. If you want a current of 10mA flowing through the LED then the resistor value is (5-2)/0.01 = 300 Ohms. A standard 330 Ohm 1/4W or 1/8W resistor should do the trick.
i just didnt want to use resisitors, but whatever thats fine. Thanks.
If you don't use a resistor in line with the LED you will blow the LED.