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Sine wave power amplification question

  1. Feb 12, 2014 #1
    Hello all,

    I'm new to electrical engineering, and I'm working on a project that requires a bit more than I'm familiar with. What I'm asking for help on boils down to this: I have a circuit that outputs a low power sine wave (frequency 25-40kHz) with an amplitude +/- 5V at a few watts. I want to amplify this sine wave signal to be at 110V RMS and 50W, or somewhere about there, it's flexible. I'm looking for some sort of IC or simple circuit that will allow me to amplify my input signal, and I was hoping for suggestions from the community.

    As a side note, would it be possible to do the same sort of amplification for a +/- 5V square wave rather than a sine wave? Is there some system that would do both?

    Thanks very much, an feel free to include as much information as you'd like, I'm hoping to learn something!
  2. jcsd
  3. Feb 12, 2014 #2
    The 110V rms is potentially lethal. If you are new to EE, I really wish you would engage a qualified EE to handle such a job. You are engaging to design a power amplifier. This is a mature well documented product, but still, if you've never designed one, I suggest you train yourself with units 24V rms or less. The 110V rms magnitude is too much for a novice. Your first mistake could be your last. Just trying to keep you safe.

  4. Feb 12, 2014 #3
    Thank you very much for your concern! At the job I work at, we build pulsed power supplies that deliver up to 30kV pulses, and I'm well trained in how to safely deal with high voltages. My lack of familiarity is in what types of IC products exist out there to do what I want. Do you by any chance have some suggestions?

  5. Feb 12, 2014 #4


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    You probably don't need to design the amp yourself. The frequency range, voltage, and power look about right for driving ultrasonic transducers for cleaning, etc. Shop around and see what you can buy before you reinvent the wheel.
  6. Feb 12, 2014 #5

    jim hardy

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    Check application notes for National LM12CLK. It's an obsolete opamp capable of 80 watts , but there are replacements. I built several projects with them before they got so expensive. The appnotes as i recall showed some clever circuits.
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