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  • #46
    Originally posted by lvanduyn
    Hi Weston..
    On looking through the parts list, I note a couple of 4000 series CMOS parts. These have been obsolete for years. I did a search of all the usual suppliers and did find the CD4060 at Jameco. I have not found the CD4022 anywhere. Most don't even have it listed and the few who do show zero stock. Perhaps you might revisit the design to see if some other chip would work before commiting to a board design.
    Thanks, Larry
    40xx CMOS not available? Oh, come on.

    Digi-Key CD4066BE, good old 14 pin DIP package, Digi-Key part number 296-2061-5-ND showing 6984 in stock, price $0.48.

    Digi-Key CD4022BE, also good old 14 pin DIP package, Digi-Key part number 296-2161-5-ND showing 1447 in stock, price $0.52.

    Both can be ordered in quantity of one. Of course, shipping would be more than the cost of the ICs but you can get almost all of the electronic parts there so just make one overall order.

    For those who are less familiar with electronic specs, the DIP style package is the type for through-hole mounting in the circuit boards. Much easier to solder than the surface mount components.

    As for lowering the current draw, I doubt that changing to a "more modern" chip, like a PIC device, would make much of a difference. Quiescent current in a 4066 is about 1 uAmp. and about 10 or 20 UAmp. for the 4022. Not much room for improvement there. Most of your current is undoubtedly going to the coils. You may save one or two milli-Amps in the rest of it, but even that much I doubt. Perhaps the oscillator section could be improved, but I don't know how. I mean you are already going through a 330K series resistor so not much current there either.

    You can program a PIC to do this but frankly, it is gross overkill.
    Last edited by Paul Alciatore; 06-27-2012, 08:36 PM.
    Paul A.
    Golden Triangle, SE Texas

    And if you look REAL close at an analog signal,
    You will find that it has discrete steps.


    • #47
      Excellent circuit Weston, could not be any easier. Very straight forward and efficient. Design current is probably at it's minimum.
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