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Charge a capacitor with minima dissipation

  1. Sep 2, 2007 #1
    I need to design a circuit to charge a capacitor with minima loss of dissipation through resistance. Any idea?
  2. jcsd
  3. Sep 3, 2007 #2
    SMPS ( Switched Mode Power Suplies ) charges capacitors through inductors and they have an efficiency of 90-95%.
    Using resistances, you lost half the power in the resistance, as stated in another thread not may days ago.
  4. Sep 3, 2007 #3
    Thank you. That is new to me and the circuit setup looks quite complicated, at least from what I saw on the net. Is there a simple circuit with inductor? Actually, all I need is a setup with minimum components that allows me to store more energy than dissipated. An efficiency of anything >50% will work. Thank you.
  5. Sep 4, 2007 #4


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    Staff: Mentor

    The simplest circuits will be using the Simple Switcher series of DC-DC converters from National Semiconductor:

    http://www.national.com/appinfo/power/switcher.html [Broken]

    Look up the application information and reference designs (and design calculators) for the "Buck" regulators -- those are the ones that take in one voltage, and regulate it down to a lower voltage using a switching transistor, an inductor, a flywheel diode, and feedback.
    Last edited by a moderator: May 3, 2017
  6. Sep 4, 2007 #5
    Thank you. Any more simpler idea to achieve just a >50% power efficiency.
    Last edited by a moderator: May 3, 2017
  7. Sep 4, 2007 #6
  8. Sep 5, 2007 #7
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