Driving 9 High power led

Other Hardware LEDs and Multiplexing
1

Hi everybody,
I have 9 High power white leds (295k mcd, 0.5W, 100mA each) that I want to dim from 0 to 255 using analogwrite(). As far as I know, each Arduino Uno pin can drive up to 40mA, so I need another way to drive my leds, but I'm new/self-taught to electronic so I'm kind of lost. I think I should use an external power supply for the leds that can handle 1A and control the power from Arduino. Should I use a transistor? How? Can I use a uA741 someway?

2

Can I use a uA741 someway?

No.

Should I use a transistor?

Yes.

How?

You need to use a constant current configuration, google for it.

3

Thanks a lot for the tip, I managed to build my current driver (rather simple, but working). XD