At least this article did define the expression for the system efficiency of the charging system, even if it did not give any numbers. I am sure that if the actual efficiency were stated that the whole concept would lose a whole lot of support. Ff course, it is a "really neat gimmick", there is no question about that, but the amount of wasted power plus the large magnetic fields should really be considered as part of the package. But thye promotors are quite aware of those numbers, which is why they are not typically displayed.
I agree with eafpres: It is indeed an important article for our readership. Aside from cell phones, Tahar, can you tell us some of the biggest applications for this technology going forward? Coincidently, Design News has an article coming up involving wireless chaging of a piece of sports equipment, which also involves TI.
I'm with Eafpres on the magnetic resonance coupling. Distance is not as big of an issue. TI should get on it. (see "witricity" for more)
When I first used wireless charging with the old Palm webOS phones, I loved it. I know that the charging base (Tx) is still tether to the wall, and you place the device (Rx) on it and so the device is still tetherd, I liked the idea of setting it down freely. It is silly to use a transformer coupler like this for using a device in bed/leasure. I would still use a plug. Any other time...it's the way to go.
My HP (webOS) Touchpad wirelessly charges to my left, right now.
If we could just focus low frequency energy as we do microwaves we could increase efficiency. So the answer may be in higher frequencies, but that also causes problems. And a dish large enough to handle 60 Hz would not fit in most cities, and thus be a bit impractical. But, it may be inefficient the way it is now, and surely can be improved, but hey, it works! And it sure is convenient!.
Hi Tahar--nice article, it seems to me that TI is really leading the world in integrated solutions for all kinds of front ends, energy harvesting, low power, and wireless applications, to name a few.
I was interested in the last part of your note; I have the impression the integrated IC you note saves board space, design time, and cost, but probably does not improve electrical efficiency. Can you clarify that?
Also, I have heard a little bit about various competing wireless charging standards; in particular I heard about a magnetic resonance technique, which I suppose is different in the mechanism of power transfer. Is TI working on any solutions for this or other wireless charging approaches?
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