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Op-amp circuits and noise at high frequency/low amplitude

  1. Sep 17, 2016 #1
    Hi everyone.

    I am tasked with amplifying an input voltage of around 1nA at anywhere between 10,000kHz to 1MHz to a sufficient amount. We've been using op-amps in multiple stages in series to amplify the signal. At our disposal we have a function generator, oscilloscope, breadboard and resistors, capacitors etc. Are there any tricks or techniques I can use to reduce the noise from the op-amps?
     
  2. jcsd
  3. Sep 17, 2016 #2

    anorlunda

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  4. Sep 17, 2016 #3
  5. Sep 17, 2016 #4

    anorlunda

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    You're wrong. it sounds like you have a false idea of what bandpass filter means. The word "band" means a range of frequencies, such as 10kHz-1MHz.
     
  6. Sep 17, 2016 #5
    Doesn't the op amp kind of work as a low pass filter? At frequencies about 1.5-2MHz+ the gain starts decreasing any way. Also we tried using high-pass filter with an RC circuit that only allows frequencies above 10,000kHz to pass and the amount of noise reduced wasn't dramatic. Is there any other tricks I can use to eliminate noise which aren't just using a filter or is my task limited by the type of op-amp I am using?
     
  7. Sep 17, 2016 #6

    anorlunda

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    I posted an answer in the original thread.
     
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