PWM dimming is done on certain LCD displays. here is an article which gives some fundamentals on this.
and here is an article on modulation.
Now here is some data on JESD204 std for serial comm.
on cellphone front, this article speaks about energy scavenging phones. I guess it'd be interesting to convert body heat, body movement back into energy, thinking of it, there are multiple opportunities:
a) body movement (peizo)
b) body or component heat/ temperature differences(thermocouple)
c) light (e.g. sunlight) (photovoltaic)
d) pressure (peizo)
e)(ok this is a bit fetchy..) crossing magnetic field of earth..
f) electromagnetic noise (I mean there are tons of devices throwing out wireless energy around rt? what if other devices can convert that back to useful energy if the signal is not meant for them?)
g) barometric pressure differences?
Ok I seem to have run of ideas for the moment, but hell yeah! why just cellphones, probably is energy scavenging or energy "recycle" going to be the next wave? There seems to be lots of "philosopher stone science" involved at the moment, but is it really far fetched as it looks like? every device has an unique environment it can adapt to. Just like the naturists say - live in harmony with the forces.. if we could apply that concept to the devices... would it not be fun? How about using the natural degeneration to power ourselves back up.. why do we still look at nuclear power with fear(different thing that every year i am proven wrong by some power plant issues somewhere).. but then, would we have even thought about power management if nuclear power was available in a cellphone? hell! we'd be running penta-core intel processors on cellphones (if it was not for the heat ofcourse ;) ). but, we get the picture..
Probably we need to think wider.. what new human interface technology has come into the market the past few years? multi-touch touch screen? we need a break through in that front, so do we need in many other fronts..
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