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Comment Smart cables (Score 1) 90

The cables have an ID chip in them that will specify their rating as to amps and voltage, plus a few other things. If you read my USB-PD story linked above, you will get the details. In short both ends start at the USB base and negotiate up their capabilities for voltage and amperage for send, receive, or both. They will do this within the bounds of the cable connecting them, and while both sides have limited capabilities to sense the cable properties, they really depend on the USB-PD ID chip.

This ID chip is of course counterfeit-proof, something we know that low end manufacturers are not capable of cloning or getting around in, oh, say, 12 seconds. So in short DO NOT BUY CHEAP/NO-NAME USB-PD CABLES FROM EVEN A POSSIBLY QUESTIONABLE SOURCE. Amazon, I am looking at you. Really. 100W = big fire quickly.

            -Charlie

Comment Re:Google is being dumb (Score 1) 90

Basically yes, but not necessarily operating the phone circuit at optimal efficiency. I think it is engineered to charge the battery as quickly as possible while minimizing damage/degradation to the cells. The charger circuitry efficiency is a big concern too, but secondary to preserving the cell life. That said this problem is optimization on a dozen axis or more, not just A vs B.

              -Charlie

Comment Re:Never fast enough will lead to disaster. (Score 1) 90

The GN7 used QC2 from what I understand, likely because of their decision to split the GS7's SoC between QC and Samsung parts. I know that the phone version used QC2 because of lowest common denominator support and I am fairly sure that carried over to the Note.

That said the problem with the GN7's fires was not a battery defect but a manufacturing/assembly problem where the batteries were physically damaged and 'crimped' to the point where they internally shorted. I should be talking to someone today who probably knows if the QC-like tech has the ability to detect and stop this. I doubt it, but I am going to ask anyway.

                  -Charlie

Comment Re:Google is being dumb (Score 1) 90

Yes. First see what the guy below said (currently ranked 0 but worth a read), and then there is the responsiveness. USB-PD doesn't have the granularity and speed to deliver power in a way that won't hurt the battery. It can't shift quickly enough of finely enough to avoid hurting the battery. Could you do the same with USB-PD? Eventually yes, but it is really designed for charging laptops and powering big monitors, not for careful charging of mobile devices.

As was said below, you effectively have to dissipate the pressure of the firehose from USB-PD, QC3 and possibly others allow you to modify the inputs to your requirements from the source. This allows you to both match your input requirements precisely and to avoid generating heat at the source (charger) rather than on the device itself. Heat is REALLY bad for battery life, that alone makes schemes like QC3 worth it.

              -Charlie

Comment Google is being dumb (Score 2) 90

Both are fine but they don't actually address what QC3 does, they just deliver more juice. QC3 will change voltage in 200mV increments on the fly, allow 2 chargers for lower temps and better heat distribution, and actively monitor the battery for conditions which degrade life. There is a lot more to it, but pushing more wattage through USB-PD is REALLY BAD FOR BATTERY LIFE. I wrote up some pretty in-depth articles on both USB-PD and QC3 lined below if you care.

This is the long way of saying what Google is asking for is idiotic. If you look at the size of modern batteries and the rate at which USB-C can deliver power, we are bordering on all-night charges already. If you up the delivered power via PD, you will not meet the 500 charge minimum life carriers demand thus not sell any phones. Worse yet that number is about to go to 800 really soon if it is not already there. Plus you will have people pissed off that their phone is drawing more current than the charger is supplying while plugged in and being used.

In short I question Google's sanity on this one. I am asking around to see what the official take on this is from involved parties, but I suspect the original article's take is way off base. I won't say why yet, I like to know before I mouth off publicly.

              -Charlie

http://semiaccurate.com/2012/0...

http://semiaccurate.com/2015/0...

Comment Re: Simple (Score 1) 322

You should check again and filter by SteamOS/Linux. Then sort by cost, you will see a fair number of triple A games there. Sure a lot are missing but my last check had over 1000 games available. If you don't NEED game-of-the-moment-X, there is plenty there to keep you happy for years.

              -Charlie

Comment Re:No, they didn't. (Score 4, Interesting) 1028

"Wipe out" is indeed what it would do.

Let's imagine this is a MIRV with 15 separate warheads, totaling 50 megatons, total (maybe). Let's imagine the targets are the following British cities: London, Bristol, Plymouth, Portsmouth, Birmingham, Sheffield, Liverpool, Manchester, Leeds, Newcastle, Glasgow, Edinborough, with the larger ones receiving two warheads.

Britain would basically cease to exist as a nation. So much damage would be done the economy would be non-functional. All the transport links in the country flow through those now destroyed cities, and that infrastructure would be destroyed. Every single piece of modern electronics in the country and in neighbouring countries that was not EMP hardened would no longer work, and everything (especially the transportation system) depends on all this stuff working. The prevailing south west winds would ensure that enough fallout would end up on surrounding areas adding to the casualties, and areas with nearby nuclear power stations would receive a lot of extra fallout. Just feeding the survivors with a barely functioning transportation system would be a logistical nightmare - ground transportation would be difficult thanks most of the major road and rail routes having been destroyed. Injured survivors would be left to fend for themselves - the entire capacity of the health service would be overwhelmed with the casualties of just one of the bombs. The electricity grid would be destroyed, even to the undamaged areas, it would be years before power was restored.

The survivors themselves, many of them would be suffering PTSD in the years afterwards, and virtually everyone will have lost friends and family and probably most of what they own in the attacks. What survived wouldn't be Britain, it would be a grotesque almost zombie like Britain with at best third world conditions for decades following.

Just because there are survivors and some land left untouched doesn't mean the country is effectively destroyed.

Comment Re: Hmm (Score 1) 1028

> You think Russia is going to bother bombing North Dakota?

Yes, absolutely North Dakota would be bombed, because that's where a bunch of American missile silos are, and Minot AFB. North Dakota might not exactly be carpet bombed but it would be the recipient of more and larger weapons than you might think.

> A nuclear war would be horrifying but it wouldn't wipe out all life on earth

No, but human life afterwards wouldn't be much fun for generations, and even after the planet had recovered, would be like pre-industrial times. A nuclear winter caused by an all out exchange would be deeply unpleasant and finish off most of the survivors. Industrial society would unlikely ever restart, given the lack of people and lack of easy to mine resources (to get much of the resources we use now requires an already existing high technology base, that would no longer exist after a catastrophic exchange of nuclear weapons).

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