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Servo Power Source — Parallax Forums

Servo Power Source

EricEric Posts: 11
edited 2009-01-13 18:41 in General Discussion
I am planning on doing some work with servos and really don't want to use a battery pack to power them.

I have a benchtop 25 Amp 12 Volt Supply that I would like to feed into a 5v power regulator. I just don't want to guess at the parts , can a standard 7805 handle a Servo?

Thanks,
Eric

Comments

  • SRLMSRLM Posts: 5,045
    edited 2009-01-13 17:26
    Yes, although you'll want to heatsink it and not draw too much current. 7 watts is quite a bit to dissipate when you're going at full power. You may want to get an intermediate regulator to spread the load out some. 9v would probably work.
  • LeonLeon Posts: 7,620
    edited 2009-01-13 17:42
    Or, use a switcher. You can even get one that looks like a 7805 (TI makes them). They cost more, of course.

    Leon

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  • SRLMSRLM Posts: 5,045
    edited 2009-01-13 18:02
    Hmmm. I've never looked at small switching regulators before. Here's one that a quick search at mouser turned up. Unfortunately, it's $10 and only 500 mA.
  • parts-man73parts-man73 Posts: 830
    edited 2009-01-13 18:41
    There is circuit described in the Datasheet for a 7805 to for Higher currents.

    It involves adding a PNP transistor and a series resistor to the input of the 7805. I've never used this circuit before, but it looks like a valid solution to the problem at hand.

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    Brian

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