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Piezoelectric Transformers

Posted by michael on from the no-more-power-bricks dept.

behoward writes "Tired of those big honking power adapters needed for all your portable toys? Me too! So far the best solution I've seen is the AC adapter for my G4 Powerbook, a sleek combo yoyo/flying saucer; but while it looks good on the desktop, it still makes too big of a bulge in my case when I travel. Now engineers at Penn State are working on a real solution. Hope Apple gets this technology in place in time for the G5 Powerbook."

5 of 190 comments (clear)

  1. Re:Piezoelectric Transformers by Malor · · Score: 2, Insightful

    Ok, so here's a couple of questions..... the piezoelectric effect is based on physical vibration. In essence, we are introducing moving parts into a power supply. This prompts the questions:

    1. Do they wear out?

    2. Will other motion or vibration cause voltage spikes or sags?

  2. Re:Piezoelectric Transformers by sfe_software · · Score: 2, Insightful

    I am doing some graduate studies in this field, so here's a quick breakdown. ...

    So if I'm understanding correctly, this is roughly equal to driving a speaker with a high voltage, and picking up the sound on a dynamic mic... resulting in a low voltage output from the mic. Accoustic coupling, only at a miniature and inaudible scale in a self-contained unit.

    Cool!

    --
    NGWave - Fast Sound Editor for Windows
  3. Re:Piezoelectric Transformers by sfe_software · · Score: 2, Insightful

    Sorry to reply again, but something occurred to me. In a normal power supply, a load on the output side directly affects the current draw on the input side. How does that work here? Other than having some kind of input-side regulation and feedback (opto-coupler?), similar to what we have now with switch-mode supplies, I'm not sure how this would work.

    By itself it seems that this technology would draw about the same amount of input current, regardless of load. Of course it's possible that it's exactly a "normal" switching supply, with the transformer swapped out in favor of a Piezo device -- in which case the other problems have already been solved.

    Any insight?

    --
    NGWave - Fast Sound Editor for Windows
  4. Re:stupid problem in the first place by Dun+Malg · · Score: 3, Insightful
    The real problem is that there is no standard connector for low DC voltage. Why isn't there one? When I travel I have to bring 9 power supplies (2 laptops, mp3 player, still camera, video camera, 2 cellphones, razor, toothbrush).

    Because there's no standard for low voltage. How many of those items use the same voltage? How many of them are even DC? Some devices are sensitive to as little as 2 volts difference plus or minus, and "low voltage" will generally be anything from 3 to 24 volts, plus they can be AC or DC. The connector isn't your problem-- it's the power your devices require.

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    If a job's not worth doing, it's not worth doing right.
  5. Re:Current products DONT use transformers by MemoryAid · · Score: 2, Insightful
    And a surge protector can get blown out by a lightning strike, too, but surges that are stoppable by the same surge protector can have been created by a lightning strike. It was just farther away.

    Isolating transformers really do work for many things, even if thesis-level detail wasn't included in some specific post on Slashdot.

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    Language students: Don't try to learn English here. This ain't it.