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USB SuperSpeed Power Spec To Leap From 10W To 100W
Lucas123 writes "While news stories have focused on the upcoming jump from 5Gbps to 10Gbps for USB SuperSpeed, less talked about has been the fact that it will also increase charging capabilities from 10W to 100W, meaning you'll be able to charge your laptop, monitor, even a television using a USB cord. Along with USB, the Thunderbolt peripheral interconnect will also be doubling it throughput thanks to a new controller chip, in its case from 10Gbps to 20Gbps. As with USB SuperSpeed, Thunderbolt's bandwidth increase is considered an evolutionary step, but the power transfer increase is being considered revolutionary, according to Jeff Ravencraft, president of the USB Implementers Forum (USB-IF). 'This is going to change the way computers, peripheral devices and even HDTVs will not only consume but deliver power,' Ravencraft said. 'You can have an HDTV with a USB hub built into it where not only can you exchange data and audio/video, but you can charge all your devices from it.'"
I have an iphone 5 and like newer samsungs and ipads these want to draw 2.1 amps from USB, which is a no-no for standard USB. THere are a number of USB hubs that pretend that they are apple/samsung compatible, promising 2.1 amps. But what they don't tell you is that you can't have 2.1 amps if the hub is connected to a computer. It will only act as a USB high current charger when it is incapable of making a serial connection. It's either a serial port or a high current charger but not both.
I'm guessing this is because a lot of devices expect their current overload regulation to come from the USB hub which is limited to 0.5 amps by spec.
Will this superspeed use the same USB plug and thus have the same limit of either being a charger or a USB port, or will it do both at the same time.
Some drink at the fountain of knowledge. Others just gargle.
because fibre optics can't carry power?
So if you have 4 USB SS ports on a motherboard that motherboard is going to have to be able to supply 400W @ 5V? You can't be serious. We'll need dedicated power connections on the motherboard just to supply this.
The example of using a TV to power multiple devices raises the same concerns. Now the TV power supply will be much more complicated. Rather than power just the 60-70W the TV draws it needs to have a power supply that could supply 100's of extra watts?
The only application I see for this is to use 100W USB SS ports on walls for a common household DC standard interface. That could be interesting, but integrating it into devices is not simple. It adds levels of complexities to the devices that will need to supply the power.
Nothing i have to say is worth saying.
Then stop wrapping them around your neck.
It will most certainly not kill you. The voltages supplied by the USB cable is far below what it needs to push enough amps through your body to disrupt any bodily function. People usually say "it's the amps that kill you", what it should say is that "it's the amps that PASSES through your body that kills you". If I remember correctly from the specs it will provide no more than 15 to 20 volts maximum. Which is still considered safe.
Repost here as I accidentally posted as AC. One of the main problems with FireWire was that it required expensive cables due to the high quality cables needed to carry the bulk power. With this spec change and the data model for SS USB, have we now got a high tech FireWire-- with all of the disadvantages and none of the advantages (I.e. daisy chaining. Guarantees about latency etc).
fairly robust fibre optic solutions to date that carry data and are far more energy efficient. im confused as to why our peripherals dont use them
Given what users can do to strain-relief-equipped multistrand copper power cables, they may not be quite ready for optical fiber...
Firewire goes to 30GB/s and 45 watts (30v @ 1.5 amps) and you can daisy chain it. Seems like a better idea than inventing a non-backward compatible serial port and pretending it is somehow related to USBs of yore.
Do you have a source on the non-backwards compatibility thing? Because the USB spec release[PDF warning] for the new USB SuperSpeed states it will be.
I should add that the newest FireWire specs only go up to 800mb/s, so also a source on that would be nice.
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
This "100watt USB!!!" nonsense has been floating around for a while, and it just never seems to get any better.
Uncertainty is Bad. 100watts is a lot of power. Your laptop's brick is almost certainly specced for less than that. Even a desktop PSU will likely be 250-350, outside of gamers and workstations(and often the upper end of the range is...optimistic... at best). Now, if we have this '100watt USB', what are devices going to do? is your next laptop going to ship with a 265 watt brick, so that it has the same 65 watts for itself as your current one does, and can handle both its ports being used? Is it going to ship with exactly the same brick and simply brown out the USB port at some unpredictable power level?(extra credit awarded if that unpredictable level depends on whether the battery is charging or not, and the current CPU load...) If "100watts" is actually "anywhere between ~15 watts and 100watts, largely unpredictable to the consumer", what are peripheral manufacturers going to target? What good is theoretical capacity that you can't actually use because a nontrival-but-hard-to-predict percentage of your customers can't actually deliver it?
Bus power is nice because it reduces cabling and complexity. However, if it isn't dependable, you can't rely on it, so you have to fall back on designs that pretend it isn't available. Now you have more expensive USB ports(in some devices) and wall warts or PSUs for your higher power peripherals! What a win!
This isn't to say that any increase in bus power is bad(given USB's use cases, 'enough power to spin up a 2.5 inch HDD' or 'enough power to charge a smartphone' are pretty useful things. However, you can't just keep pushing the ceiling without limit: the wider the uncertainty, the greater the costs(for devices that actually engineer to spec and include the capability to support the top of the range) and the greater the limits and confusion(for devices that target more realistic real-world output values, and for the poor bastards who think that 'USB' means 'works when plugged into my USB port').
OTOH 20 amps is enough for a USB powered Tesla coil, which might kill you.
Can't wait!
No sig today...
because fibre is much easier to break/snap than copper. Same reason the company my friend works for who installs media distribution systems into Lufthansa aircraft don't spec it out with fiber lines.. they use CAT 7 with the TERA style ends, because an over-zealous mechanic is more likely to snap a fibre optic line with his zip tie than a copper line
While I'm not impressed by USB's mutations over the years, Firewire had the major drawback that(at least in practice, not sure if the paper demanded otherwise) there was a very, very heavy emphasis on 'up to' when it came to how much power could be delivered.
A small minority of actually-well-built workstations and the like wouldn't shrug at providing full specced power. More or less ordinary PCs usually had a floppy or molex connector to supplement PCI bus power; but didn't spring for a DC-DC converter, so (since 30v isn't readily available anywhere on the DC side of an ATX PSU) you generally got 12v, albeit at a decent amperage. Laptops? In practice, "firewire" pretty much meant 'whatever Apple did on the last couple of models of ibook and powerbook; because all the PCs omitted the power pins entirely for "i.link" or similar, which usually boiled down to ~19v, if on adapter, 12-ish if on battery.
The nominal maximum was certainly fairly spacious; but a powered firewire peripheral was essentially always on the hook for a DC-DC converter, and had to deal gracefully with(or simply refuse to work with, ideally in a documented way) substantially inferior power supplies from many devices.
5v 500ma was always pitiful; but (by virtue of being so pathetic) most devices actually did as well or better than they claimed to, and lots of peripherals could get away with only the cheapest of designs for handling bus power.
That's my bet for why "100watt USB" will suck. Sure, it'll be cute and all that POS hardware vendors can now have USB printers and things that are 'standards compliant' and will actually work if purchased 100% from approved vendors and plugged in just right; but everyone else will have wildly unpredictable actual power levels.
The main benefit of TOSlink is avoiding ground loops in audio systems. This is especially important if you have a long run between ends of the building with a significant resistance in the building ground system between them.
People have no appreciation for the amount of power it takes to run a fully armed and operational battle station.
the growth in cynicism and rebellion has not been without cause
Odd, I thought using zip ties was illegal on aircraft. Due to the fact that they can cause vibration damage to cabling, and make it wear through exceptionally quick. While it's been awhile since I was last at a fab plant, they were using low abrasion cloth such as silk to tie cabling together.
Om, nomnomnom...
Ever tried putting 5v @ 20A though a PCB trace?
Yes, but I still pretend I didn't.
Never speak of it again.
"I've got more toys than Teruhisa Kitahara."