- Wed Dec 16, 2015 4:30 pm
#186604
I am looking at using the 3 watt led https://www.sparkfun.com/products/13105.
I have read and think I understand the hookup guide for the femtobuck.
https://learn.sparkfun.com/tutorials/fe ... -guide-v12
What I am wondering is can the same thing be accomplished by a simple n channel mosfet? I saw a couple of other tutorials where the PWM from an Arduino is connected to the gate, and the other pins of the mosfet connected to ground and the led which is also connected to a higher external power source. Sometimes I see a 100ohm resister on the PWM pin. This seems electrically a lot simpler than the femtobuck. The femtobuck however provides a constant current, designed for the LED's, and I can't quite see how the mosfet will be able to control the current through it.
Anyone able to explain better how the mosfet would work in this example. (I did watch Pete's old tutorial) Is it better (what reason) to stick with the femtobuck?
Thanks,
Chris
I have read and think I understand the hookup guide for the femtobuck.
https://learn.sparkfun.com/tutorials/fe ... -guide-v12
What I am wondering is can the same thing be accomplished by a simple n channel mosfet? I saw a couple of other tutorials where the PWM from an Arduino is connected to the gate, and the other pins of the mosfet connected to ground and the led which is also connected to a higher external power source. Sometimes I see a 100ohm resister on the PWM pin. This seems electrically a lot simpler than the femtobuck. The femtobuck however provides a constant current, designed for the LED's, and I can't quite see how the mosfet will be able to control the current through it.
Anyone able to explain better how the mosfet would work in this example. (I did watch Pete's old tutorial) Is it better (what reason) to stick with the femtobuck?
Thanks,
Chris