Noobish LED Question

Other Hardware LEDs and Multiplexing
1

Hello all.
First and foremost, thanks in advance for your time for a newbie like me. I also apologize in advance if I make a lot of mistakes.

For a project I am working on, I need to light 6 leds (at the same time) with a single arduino digital pin. Is this possible? If so, what kind of hardware would I need? How should I wire the leds?

I would like to be able to simply 'digitalWrite' 'HIGH' to the pin and have all leds come on, with a decent level of brightness. The leds I plan to use (if they will work) are these:
http://www.amazon.com/Bluecell-Green-Electronics-Bulb-light/dp/B006G6TKQW/ref=sr_1_3?ie=UTF8&qid=1389495910&sr=8-3&keywords=green+leds

Regards,
TechnoD

2

The Forward Voltage Drop is reportedly 3.0 to 3.4 Volts. That means if you want to put six in series you will need more than 20.4 Volts which seems a bit high. With 12V you could make two strings of 3 and use an NPN transistor to switch them on and off.

If you only have 5V available you will need a current limiting resistor for each LED but the negative sides can all got through a single NPN transistor to turn on and off.

Search for an online LED calculator for resistor values.

3

You just need a transistor rated for enough current to power them.