I need to drive 2 led ir with arduino. The led max output is rating as 50mA but I know they can draw over to 1A with pulse. Can anyone tell me a circuit diagram for driving it with a 2n2222 transistor? Thanks
What is the forward voltage drop of your LEDs? What is the LED supply voltage?
You are suggesting that they can be used to be driven at up to 1A, if you do so, you will need another transistor as the 2N2222 is not suitable.
What power supply are you using? If the 5v onboard you are limited in current.
Assuming you are wanting to use the onboard 5v and only want limited current, the LEDs can probably be connected in series and controlled by the 2N2222. This depends on their voltage drop as queried previously. You will need 10k resistor to the base of the transistor and a current limiting R in series with you LEDs. The value depends on the current required. If simply low power LEDs in series, 100 ohms would do.
Weedpharma
I don't know the led supply voltage, as it don't have any info available on the packet! Anyway I tried with a 220ohm resistor on the resistor and it seem to work great.