LTspice model for CD4017?

Discussion in 'General Electronics Chat' started by wayneh, Oct 27, 2014.

  1. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    I'm unsure of the inputs to the 4017 symbol. I've gone to the Yahoo group to get the CD4000_v.lib file, the CD4000 symbols folder and the instructions, and I have successfully added the symbol and model to my project.

    But the I don't get what those 3 inputs are. I need Reset, Clock and Enable. It appears they are listed top-down in that order on the symbol, but I'm not sure. Do you agree?

    Screen Shot 2014-10-27 at 10.28.25 AM.png
     
  2. ericgibbs

    Senior Member

    Jan 29, 2010
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    hi,
    Reset, /CP1 and CP1
    E
     
  3. Papabravo

    Expert

    Feb 24, 2006
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    Why do you think the inputs on the symbol are something else?
    R=RESET seems obvious.
    You can configure the "Clock" to have either an active high enable or an active low enable. Whichever input is used for the enable, the other input is the clock. That is the meaning of the half circle that looks like an AND gate.
     
  4. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    Just good old ignorance. My chip has an "E" pin and the symbol doesn't. Your explanation makes sense as to why that is.
     
  5. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    Now I'm having a different issue with the 4017 model:
    Screen Shot 2014-10-27 at 12.20.28 PM.png
    This model is supposed to allow using the actual circuit voltage as entered into the attributes for the symbol. Whether I edit the default Vdd=5 or leave it alone, it resets itself to 5V and throws this error at me. What am I missing?
     
  6. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Try adding a label 'Vdd' to the 4017 positive supply point (or a node at the same potential).
     
  7. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    The symbol provided for the 4017 (posted in #1) does not have supply pins.

    BUT, the trick is to add a "Net Name" of Vdd to the positive rail of the power supply. Works like a charm now! That's probably what you meant?

    Thanks.
     
    Last edited: Oct 27, 2014
    Delian Diver 1 likes this.
  8. ericgibbs

    Senior Member

    Jan 29, 2010
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    hi,
    Please post your asc file so that we can see how its connected.
    E
     
  9. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Yes, provided that rail is the 4017 supply. (There may be more than one +ve rail in a circuit.)
     
  10. wayneh

    Thread Starter Expert

    Sep 9, 2010
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    Yes indeed, it is.
     
  11. Papabravo

    Expert

    Feb 24, 2006
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    Sometimes the internal logic is conveyed by the symbol and sometimes it is obfuscated. Glad you were able to resolve the situation.
     
  12. eetech00

    Active Member

    Jun 8, 2013
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    Hi wayneh

    Here is a little demo circuit.

    I've also attached a zip with the circuit and new symbol if you want to use them.

    eT:)
     
    Delian Diver 1 and wayneh like this.
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