One of the last speakers at the Plenary today was Qualcomm executive Franceco Carobolante. He explained that the best frequency with which to wirelessly charge your Kindle or cell phone was 6.78 MHz. One reason for that is if you were to use 100 kHz instead of 6.78 MHz for wireless charging, you might find your stray chewing gum wrapper heat up another 50 C. They do test to make sure that just in case you fall asleep with your head on the wireless charging mat you will not cook, either. It does rub me under the skin that wireless charging is much less efficient than the traditional methods of charging. The point he made was that it only cost another $1/year in energy to charge your cell phone wirelessly. That is another 10 kilowatt hours of power just to run the thing.
In today’s Plenary session, Dr. Umesh Mishra spoke of his parallel concept of Moore’s law (Intel) to the scaling of power supply density with time. Who knows? It might just become “Umesh’s Law”. Using examples from Bipolars, IGBT and DMOS, he reminded the audience that over the last 40 years semiconductor components have helped scale the convertor’s power density. His point was that for the last 10 years we have flatlined improving the power devices. Of course, this leads back to our industry’s need for GaN or SiC to force the industry back on the “ Umesh law” power-density scaling curve. He did skip the fact that there have been major improvement in devices like super junction.