Timing time delays and checking drive capabilities of a TTL IC

Discussion in 'The Projects Forum' started by amjg92, Mar 13, 2011.

  1. amjg92

    Thread Starter New Member

    Dec 14, 2010
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    Hi,
    I have a project where I have to find the time delay and the drive capabilities of a TTL gate. ex of a 7404 inverter... i know I have to vary the voltages for drive capabilities and plot some graph but i have no idea what to do for the time delay. Something as easy as possible is prefered. Any idea how pls? thanks beforehand
     
  2. jmdejoanelli

    New Member

    Mar 13, 2011
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  3. amjg92

    Thread Starter New Member

    Dec 14, 2010
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    Yes but I need to devise an experiment on how to find these :/
     
  4. Papabravo

    Expert

    Feb 24, 2006
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    Most datasheets have test circuits that show how various measurements are made. Have you looked at the datasheets??
     
  5. amjg92

    Thread Starter New Member

    Dec 14, 2010
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    I have searched for datasheets I found some which gave graphs but did not find and method of obtaining measurments
     
  6. Papabravo

    Expert

    Feb 24, 2006
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  7. CDRIVE

    Senior Member

    Jul 1, 2008
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    Not sure what you mean by this. TTL is 5V standard that has to be kept within the lower and upper limits of 5V in order for it to operate properly. Each chip is also rated for maximum 'Fan Out' that specs how many TTL inputs it can drive.

    Sorry if I've misinterpreted your question.
     
  8. amjg92

    Thread Starter New Member

    Dec 14, 2010
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    at CDRIVE. I need to know the proper limits where the TTL begins to read the voltage as LOW and the Voltage as HIGH like the boundary conditions.
    @papabravo This is very helpful thanks
     
  9. Papabravo

    Expert

    Feb 24, 2006
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    The delay measurements can be done with a two channel oscilloscope.

    The tables showing input and output HIGH and LOW voltages should give you some clues about how to set up an experiment. You need an adjustable voltage source on the input and you need to be able to locate the switching points.
     
  10. CDRIVE

    Senior Member

    Jul 1, 2008
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    Google and AAC is your friend. This took me all of 20 seconds to find.
    http://www.allaboutcircuits.com/vol_4/chpt_3/10.html
     
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