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Hobby motors

David W.David W. Posts: 6
edited 2005-01-11 04:53 in General Discussion
· Hi

·I have been learing to use the BS2 for some time now on my ou and tring
a project that i need to turn some hobby motors on and off and· not shore
how what to use the motors run on 3v and draw up to .500

thanks
David

Comments

  • Jon WilliamsJon Williams Posts: 6,491
    edited 2005-01-02 21:27
    You can use a MOSFET to switch the motor for you.· Have a look at the attached schematic.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Jon Williams
    Applications Engineer, Parallax
    Dallas, TX· USA
    Motor_MOSFET.GIF
    400 x 527 - 11K
  • MacGeek117MacGeek117 Posts: 747
    edited 2005-01-03 18:30
    Or you can use a H-bridge if you want forward/backward control.

    look for the L293 dual motor driver chip. -bugg
  • David W.David W. Posts: 6
    edited 2005-01-10 23:43
    Hi, my name is David Warren and I am a machinist by trade and I don't work with electronics very often. So I apoligize if some of my questions seem a little strange or repetitive. I have a good basic understanding of electronics and I can follow most scematics however some components I am not totally familar with. I got into Basic stamps thourgh my brother when he gave me a bs2 to try to use to control a halloween prop. So now to my question In a previous posting I asked about turning a hobby motor on or off, this is all I need to do I do not need any direction control and one of the replys I was told I could use a Mosfet transistor. The one that I have is from Radio shack it is an n channel and on the back the maximum ratings are VDSS=100v, VGS=+ or - 20v, with an IP = 4A, the part number is a Radio shack 276-2072 and the packaging says IRF510 power Mosfet transistor. I was wondering if· this would work, the motor as I previously stated uses 3 volts and draws .500A. The Diagram on the package does not show a diode as in the scematic attached to one of the postings from Jon Williams. Or is there a better Mosfet that I should be using? I certainly apologize for the rambling. Thank you for any assistance that you can give to a novice like me. Please excuse the spelling errors.

    Thanks David Warren
  • Paul BakerPaul Baker Posts: 6,351
    edited 2005-01-11 04:53
    The ratings you quoted are max ratings, and your app falls within them.· Radio shack boxes are not always the most accurate in the
    world, a quick check ( http://www.irf.com/product-info/datasheets/data/irf510s.pdf·) shows that indeed the part has a flyback protection diode in it. Ordinarily I'd say go for it regardless, but you are driving an inductive load (all the windings in the motor = one big inductor) and that is the reason the FBP diode is there, because when you switch the motor off, the electric field stored in the motor windings will collapse and cause an outrush of current. The diode provides a safe path to ground, protecting the FET.
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