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Increasing voltage using operational amplifier

  1. Apr 5, 2017 #1
    I want to build own circuit using operational amplifier and resistors. I have 12V power source (car accumulator) and 6V input voltage (Vin). I want to get 12V Vout and 25W at the output. So that is about 2A current(25/12=2).

    I heart that operational amplifiers (OA) work only in low currents. Therefore I am not sure that it is appropriate to use OA to implement my aim.

    My aim is to get 12V voltage and 25W power at the ouput from input voltage Vin=6V and 12V power source(car accumulator) using following circuit.
    So is this appropriate circuit? If, no can someone provide alternative curuits? Thanks!
  2. jcsd
  3. Apr 6, 2017 #2


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    ok so a 12V car battery

    What is this 6V in you are talking about ? 6V into what ?

    so why are you not just taking the 12V from the battery directly ?
    what are you wanting to power ?

    You cannot get more power out of something than what you put into it.... in fact there will ALWAYS be less power out due to various losses
    Reread the last sentence in the graphic you posted

    you really need to read up on OP-Amps and how they work

    here's a good starting video .....


    Last edited: Apr 6, 2017
  4. Apr 6, 2017 #3


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    If you want to have an output greater than the supply voltage, you must use a specialized circuit. In short: You chop up the input voltage into a pulse train, use inductors or capacitors to increase the amplitude and rectify the result.

    Start by reading this application note : http://cds.linear.com/docs/en/application-note/an19fc.pdf
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