Connect with us

PWM DC motor circuit?

Discussion in 'Electronic Basics' started by Terry Pinnell, Jul 10, 2004.

Scroll to continue with content
  1. Steve Taylor

    Steve Taylor Guest

    I saw that, but will Terry "already have code for simple things like PWM"

  2. Definitely not!
  3. Al Borowski

    Al Borowski Guest

    OK, fair enough.

  4. John Jardine

    John Jardine Guest

    Same here :).
    Cars used to be ripe for mod's that the makers now offer as standard. The
    last car had a couple of motors and a joystick just to set a wing mirror.
    It's crazy the level of technology that can be offered.
    I'm a keen DIYer, so years ago realising the cars were becoming a lost
    cause, changed tack and pursued home automation projects.
    Come the present day and I find the manufacturers have caught up yet again.
    No corners seemingly left untouched.
    I go down to the Lidl supermarket and buy 'Energy usage analysers' (real and
    apparent power, frequency, true RMS Watts, Voltage, current, power factor,
    accumulating costs totaliser) for an unbelievable £4.99 (last month I bought
    another 4!).
    They've also sold me sets of 4 beautyfully engineered, remote controlled
    (433MHz)power sockets at £12. Last week from Aldi's I bought 3 super
    quality DVM's at £5.99 ea. A radio controlled timepiece? that'll be £12 sir.
    Battery operated PIR lighting a snip at £2.99. Remote garage door opener £52
    please. The list seems endless.
    They won't realise it but the far Eastern manufacturers are ruining my will
    to live :).
    I bought a Chinese milling machine a couple of years ago. A 1/3 of the UK
    price and better quality. It's something I would have enjoyed taking a year
    to make homebrew but at that price it was a no-contest.
    Don't know about all the other guys here but what I enjoy most is the
    '-journey-', the end result (or more likely, not!) is a bit immaterial. I
    like to think though before embarking on a pet project, that it has a bit of
    a novelty value. If I suspect that there's something already on offer
    (cleverer, cheaper, more reliable, more features) then a bit more of that
    essential joie de vie, is chipped away.
    (Post some pictures of the curtain opener if you complete ).
  5. Bob Wilson

    Bob Wilson Guest

    Already have the code? That's cheating! I could say that I already have
    the PWM built up too! :)

    My comment was actually intended for a wider audience, and assumed that
    the builder would not just happen to have parts of it (or the code for a
    micro) already in existence.

    I guess I'm the opposite of you. I don't happen to have a PIC (or its
    code) lying around, but I do have tons of LM339s and all standard values
    of resistors and caps at my fingertips.

  6. John Jardine

    John Jardine Guest

    Good point.
    Have just redesigned 3 small low cost gp 'timer-switch' type sm PCB products
    (costs equiv to 2 USD ). Minimum cost was the design target. 2 of the
    existing designs used PICs. It proved 25% cheaper (and a better spec') to
    redesign just using discretes. (I do have PICs and code snippets to call on
    if a job warrants it).
    The PICs are not a general panacea and I've seen more than a couple of
    occasions where PICs had been badly used because their programmers clearly
    didn't understand the analogue stuff (to my benefit of course:).
  7. Gordon Youd

    Gordon Youd Guest

    MFACOMO DRILLS sell a PWM module which allows infinitely variable motor RPM
    to be set.

    About 1 inch cube, 2 wires in, 2 wires out with a screw to set the speed.

    Rapid electronics also sell them, they are about £8.00.

    Hope this helps.

    Regards, Gordon.
  8. Thanks, Gordon. I'll take a look at that. However, at the moment, it's
    looking just possible that I can get away with the raw supply. I'm
    using the original 2.4 V and under the load of the curtain it's a
    manageable speed.

    Terry Pinnell
    Hobbyist, West Sussex, UK

Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day