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Voltage to voltage converter

  1. Sep 26, 2010 #1
    Our Transistor is a Voltage to Current converter can we form a Voltage to Voltage converter too physically or not??
    can someone help me in this matter plzz
     
    Last edited: Sep 26, 2010
  2. jcsd
  3. Sep 26, 2010 #2
  4. Sep 26, 2010 #3
    Actually a transistor is a current to current amplifier.
     
  5. Sep 26, 2010 #4

    Averagesupernova

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    For the record, I agree with post #3 but there has been alot of discussion/disagreement on this. Quite possibly on this forum. How a transistor circuit is configured determines what the circuit is as a whole concerning voltage and current, etc.
     
  6. Sep 27, 2010 #5
    guys i mean that we can make a voltage to voltage converter by just adding some resistor,,can it be possible in daily life that we input voltage and in return we get voltage too.if so then wat in case of adding a capacitor at the output????,in that case we are also getting voltage at the output but for dc source capacitor will open and circuit will nt work.
     
  7. Sep 27, 2010 #6
    This sounds like a discussion in semantics....a transister requires current AND voltage at the input and produces an output with a current AND a voltage....the configuration, emitter,base, collector, ground, etc depends on what you are trying to accomplish....that is, the application.

    As an example, you can call a transformer a voltage conversion device, because that's usually wheat we are interested in accomplishing, but it involves the flow of current as well and both must be taken into account in design. If you want to make a step up transformer, for example, say 120 volts in and 240 volts out, too small a wire size and improper resistance in either the primary or secondary will cause the wire to overheat and maybe a fire....
    http://en.wikipedia.org/wiki/Electrical_transformer
     
    Last edited: Sep 28, 2010
  8. Sep 27, 2010 #7
    If your output voltage is to be less than your input voltage it is very easy to convert the input voltage to the output voltage. If the output voltage is to be a percentage of the input voltage and the load will be high impedance then a simple resistive voltage divider will work. If you want a constant voltage out with a varying input voltage or a varying load then you can use a voltage regulator.

    However, if you want your output voltage to be higher than your input voltage, then the input must be converted to AC, transformed to a higher voltage, rectified and filtered to remove the remaining AC. This may be the purpose of the capacitor.
     
  9. Sep 27, 2010 #8

    vk6kro

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    If you want an output which is greater than the input voltage, you could also use an opamp.

    Depending on the ratio of a pair of resistors, you can have an output which is directly related to the input by the same ratio as the ratio of the resistors, as long as you don't need the output to be greater than the supply voltage.
     
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