help..

Discussion in 'Homework Help' started by shivanibindu, Jan 17, 2012.

  1. shivanibindu

    Thread Starter New Member

    Jan 16, 2012
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    i am a beginner in LTspice and wish 2 do a 10 bit adder circuit.
    so plz.. anyone explain me how could i declare a single bit component as my on.
    actually i had don one bt itz not wrkng, while running it shows "node missing". n am using LTspiceIV.
     
  2. RRITESH KAKKAR

    Senior Member

    Jun 29, 2010
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    You must be using 74xx or 40xx series chip in spice so, it would require spice directory for that.
    something like this .inc 74hc.lib and .inc CD4000.lib
     
  3. shivanibindu

    Thread Starter New Member

    Jan 16, 2012
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    hi rritesh...
    srry.. i dnt get that. In spice directive v hav 2 specify the file path, rgt??
    n the error shown is "unknown controllng source n002".
    can u plz help..
    am nt so familr wth spice.
     
  4. RRITESH KAKKAR

    Senior Member

    Jun 29, 2010
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    Can you post the screen shot by pressing print screen on keyboard then paste it to paint.
     
  5. shivanibindu

    Thread Starter New Member

    Jan 16, 2012
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    thnks 4 ur consideration..
    ckt is single bit fuladder using cmos.
     
  6. RRITESH KAKKAR

    Senior Member

    Jun 29, 2010
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    You have not mention that you are using MOS to build adder..!!
    Have you ever used MOS?
     
  7. joeyd999

    AAC Fanatic!

    Jun 6, 2011
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    Why do you want us to work so hard trying to interpret your l33t speak???
     
  8. MrChips

    Moderator

    Oct 2, 2009
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    As a new member there are some rules you have to learn.

    1) Never post a title such as "help..". Express yourself clearly as to what the topic is about.

    2) Write clear English, not textese. Make sure you can be understood.
     
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  9. shivanibindu

    Thread Starter New Member

    Jan 16, 2012
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    sorry sir, its my mistake i regret deeply for it.

    I wish to compare the performance of a CMOS 10 bit ripple carry adder and a CMOS 10 bit carry look-ahead adder. But i am unable to declare CMOS single bit full adder as a component . So would you please help me to solve this problem ?.
     
  10. RRITESH KAKKAR

    Senior Member

    Jun 29, 2010
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    I have already said use 74xx or 40xx adder chip, using MOS will be more complicated.
    The chip work on GND and Vcc(5V) but in MOS this not true.
    Different MOS require diff gate voltages.
     
    shivanibindu likes this.
  11. shivanibindu

    Thread Starter New Member

    Jan 16, 2012
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    Thank You.
     
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