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Momentary push Neg to off-on-on switch

Discussion in 'General Electronics Discussion' started by shadowflare99, Sep 11, 2012.

  1. shadowflare99

    shadowflare99

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    Aug 7, 2012
    Can you help me

    i want to build a another project, and this one

    i need to push a momentary switch with negative output, (normaly open)

    and first push wil active one relay, second push will active the first relay and another relay, and third momentary push will OFF Two relay,

    can you help me ?
     
  2. CocaCola

    CocaCola

    3,635
    4
    Apr 7, 2012
    I would do this with a micro, but you can also do it pretty simple with a 4017 as well...

    You will need a hardware debounce circuit if you do it with a 4017... There is a simple hardware debounce circuit here...

    http://www.elexp.com/t_bounc.htm

    The 4017 is a counter, with each pulse (button press) it steps up a ladder...

    So on that ladder:

    The first output is not connected (this is the idle stage upon power up, doing nothing but waiting for a button press)
    The second output goes to relay 1
    The third output is split to relay 1 and 2
    The forth output is tied to reset

    You would need to force a reset of the 4017 upon each power up so that the chip doesn't start at some random position on the ladder... That can be done with a 0.1µF capacitor from RESET (15) to VDD (16), and a 10K resistor from RESET (15) to VSS (8)

    Note the 4017 can't drive the relays directly, so you will need to have the 4017 drive a transistor that drives the relay...
     
    Last edited: Sep 12, 2012
  3. shadowflare99

    shadowflare99

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    Aug 7, 2012
    and how transistor work ??

    and also the with the 4017 i suppose the input was a positive form ??
     
  4. CDRIVE

    CDRIVE Hauling 10' pipe on a Trek Shift3

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    May 8, 2012
    It's triggered on a logic 0. You can drive the relays with a Darlington transistor array like a ULN2003.
     
  5. shadowflare99

    shadowflare99

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    0
    Aug 7, 2012
    Last edited: Sep 13, 2012
  6. CocaCola

    CocaCola

    3,635
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    Apr 7, 2012
    You have the basics down, Q3 would be tied to reset on the counter to send the chip back to Q0...

    Q2 would be "Y" connected to that two devices you want to trigger at that time...

    May I suggest you bread board the actual design 'simulators' are great but many fail to simulate everything properly... Things like debounce of the switch are taken for granted in many simulators, in the real world you need to compensate for this effect... Using the simulator to get a generally idea on how it works is great, but sometimes those missed little issues will come back to bite...

    It's also a cheap circuit to build and play with, pick up a few CD4017 as they can be prone to getting toasted from static when handled and not permanently mounted in a circuit... They are only a few cents and fun to play with :)
     
  7. CDRIVE

    CDRIVE Hauling 10' pipe on a Trek Shift3

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    648
    May 8, 2012
    I don't want to load the Java Plug-In. Do you have a way of copying it and posting it here as a jpg?
     
  8. shadowflare99

    shadowflare99

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    0
    Aug 7, 2012
  9. shadowflare99

    shadowflare99

    29
    0
    Aug 7, 2012
  10. CocaCola

    CocaCola

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    Apr 7, 2012
    I can't see you circuit simulation on my laptop as you used a huge resolution and I can't view at that resolution so I only get a corner of the circuit... I have no idea what you built to even give advice...
     
  11. shadowflare99

    shadowflare99

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    Aug 7, 2012
    use ALT key to move the simulation...
     
  12. CocaCola

    CocaCola

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    Apr 7, 2012
    The Alt works to shift the circuit around but I can still only see a small section at a time, never a complete overview... Also what do you mean by "Clock (14)"?
     
  13. shadowflare99

    shadowflare99

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    0
    Aug 7, 2012
    well it's something like that but only IC3
    http://www.elecircuit.com/automotivecircuit/Fan_Speed_Control_Circuit_with_IC_CD4017B_1611.html
    and Q1-Q2 on relay ... and Q3 will reset. ..

    i try on my lab board ... the relay open and close very fast ... and when i touch a + 12 on Clock .. nothing happen

    16 VDD on Ground
    8 12+ on 12+

    like the sheet ... 8-13-15 on ground ...

    nothing to 14 :...

    Q1-to Q9 ... nothing arrive
    some of these have 0 Volt many have 0.33 V on it ...

    But Q0 have 12 Volt ...
    Q1 have 3.5 Volt ...
     
  14. CocaCola

    CocaCola

    3,635
    4
    Apr 7, 2012
    Do you have this circuit built? If so take multiple detailed photos so that we can look at it...
     
  15. davenn

    davenn Moderator

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    Sep 5, 2009
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