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Optimizing astable multivibrator for minimum power consumption

  1. Sep 16, 2011 #1
    In short, if I want a given frequency, and I use BJT transistors, what would be the optimum capacitors and resistors in a multivibrator.

    http://upload.wikimedia.org/wikipedi...tivibrator.svg [Broken]

    So, what are the optimum values C1=C2, R1=R4, and R2=R3?
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Sep 18, 2011 #2
    Don't use transistors.
    Use operational amplifier Nation Semiconductor type LMC6041.
    Use circuit figure 11 from LMC6041 data sheet.
  4. Sep 18, 2011 #3
    I know the best way to go is to get the thing built on a chip. I was trying to understand how the chip works in terms of components I understand--i.e. transistors, resistors, capacitors, and diodes.
  5. Sep 18, 2011 #4
    This is not my area of expertise, so someone correct me if I'm wrong.
    Use the lowest power transistors available. ? Probably FET or JFet transistors?
    The energy stored in the capacitors each cycle is wasted, so use the lowest possible capacitance.
    Use the lowest possible operating voltage.
    Use the highest resistance resistors possible.
    The actual value of the resistors and capacitors will depend on the transistors that are used, the wave shape requirements and the load impedance.
  6. Sep 19, 2011 #5
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