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Nanowatt switch?

  1. Feb 23, 2013 #1
    I am looking for equivalent of relay or optocoupler but in nanowatts range if there is any.
    I looked into a MOSFET however gate switch cannot be isolated and there is Id drop when conducting. Relay is cool because there is no current drop or voltage drop when switch is on. Timing is in millisecond range.

    ----- ------- switch

    ---=====----- trigger input

    however trigger input has coil which has consumes lots of watts.
    Optoisolator has losses in both ways (switch and trigger input).
    Voltages are of 0.4V minimum to 2V maximum. Currents are in low mAmps.
  2. jcsd
  3. Feb 23, 2013 #2
    You will have to take care about thermal noise V=4kTBR in every resistor and shot noise in every flowing charge.
    Use a very restricted bandwidth B. A sharply tuned circuit (Care - it limits rapidity of response)
    Use NO RESISTORS. Use parametric amplifiers (work by varying L or C)

    Good luck - you deserve it for trying.

    The human eye (one photon) and the human ear (120 db power range) are good inspirations!
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