comparator

Discussion in 'Homework Help' started by harsha a s, Jan 25, 2012.

  1. harsha a s

    Thread Starter New Member

    Jan 23, 2012
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    sir, actually am getting an volatges which varies from (0-10). now i need to pass this voltage to a circuit which gives me either low or high condition depending on the vref which i give... so can i get a help about which circuit or ic will be useful for this????
     
  2. Georacer

    Moderator

    Nov 25, 2009
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  3. holnis

    Member

    Nov 25, 2011
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    You may Use the voltage comparator integrated circuits such as the LM339 Quad Voltage Comparator chip or the LM393 Dual Voltage Comparator chip. These devices are functionally identical. The LM311 Voltage Comparator can be used for your application as well and also has a number of unique features.

    Note that, The LM339, LM393 and LM311 comparator chips can operate from a single or dual power supply of up to 32 volts maximum.
     
  4. Audioguru

    New Member

    Dec 20, 2007
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    Sometimes an opamp is used as a comparator but it switches its output fairly slowly.
     
  5. harsha a s

    Thread Starter New Member

    Jan 23, 2012
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    actu i must feed dc voltage to a comparator. so ill lm339 works??? and usaully what output an lm339 ill give???
    like will it gives either 0(low) and 1(high) based on Vref..
    or will the output increases once Vin crosses Vref???
     
  6. harsha a s

    Thread Starter New Member

    Jan 23, 2012
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    0
    sir, i have input voltage varying from (0-100)v so now i need a circuit which gives output either low(0) or high(5) based on Vref.
     
  7. Georacer

    Moderator

    Nov 25, 2009
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    The lm339 can't handle nearly as much as 100V at its input. You will need to use a voltage divider and insulate it carefully. How did you acquire such a high voltage anyway?

    I suggest you take a look at the lm339 datasheet (http://www.datasheetcatalog.org/datasheet/nationalsemiconductor/DS005706.PDF) where you can find some typical application circuits, as well as its maximum ratings.
     
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