Shop OBEX P1 Docs P2 Docs Learn Events
Driving 2A w/ prop — Parallax Forums

Driving 2A w/ prop

RottenJalapenoRottenJalapeno Posts: 27
edited 2008-08-09 12:57 in Propeller 1
I am working on a project that needs roughly 2A worth of led's driven by a prop chip.
I am looking for something as cheap as possible, and I want to be able to Pulse-Width-Modulate them as well to control the brightness.· I was looking at some darlington power transistors, but I couldnt find any that could drive 2A and still be switched by the prop.· If anyone knows of a p/n for something that would work I would love to hear it.
Thanks for the help,
Jeremy

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2008-08-09 12:48
    Why wouldn't a Darlington power transistor work? A TIP120 is $1.30 at RadioShack and much cheaper elsewhere and will easily switch 2A. I'd use a 220 Ohm or 330 Ohm base resistor to limit the base current.
  • Erik FriesenErik Friesen Posts: 1,071
    edited 2008-08-09 12:57
    Seems to me that a npn-pnp combo should work.· I'd order plenty of stuff and just start experimenting.

    I am using a on semi mjd32 from mouser that the data sheet says can handle 3 amps(with heatsink?).· I am driving it with a small npn and using the prop counters to control the power level.··
    pdf
    pdf
    schem.pdf
    18K
Sign In or Register to comment.