SONICable Promises To Double Mobile Device Charging Speed Over USB

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weilin

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I wonder how they're pulling this off considering how USB 2.0 ports are rated at 500ma. Attempting to draw any more than that may compromise the stability of the computer...

Does turning syncing and data off really decrease the power draw of an device enough to double the charging speed?
 

masterchi

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Feb 6, 2015
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"While the SONICable claims to increase charging time when plugged into a computer...", isn't it suppose to decrease charging time?
 

alextheblue

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So if you charge exclusively via standard USB 2.0-type microUSB or Lightning cables on a PC, laptop, etc then it potentially doubles your charging speed (possible excluding devices offering ports designed to charge devices faster) . But if you already use a dedicated 1A+ charging source such as a typical modern USB power block, then it's pointless.

More importantly, are there any brands/designs of 6-ft+ Lightning cables that really hold up for a long time? I've got family members with iPhones and a good quality 3 ft cable seems durable enough, but we've had even supposedly premium long MFi cables fail prematurely (after anywhere from couple months to almost a year). This is kind of mind blowing to me since I use microUSB and I can't ever recall having an undamaged-looking microUSB cable simply cease working. I've got a couple of long cables that are a few years old, cost a fraction of what an MFi lightning cable costs, and are still working perfectly. Meanwhile they kill at least a couple cables a year. Bad luck? Fake MFi certs?

What really got me curious is the fact that Apple does not sell first-party cables longer than 3 feet.
 

alextheblue

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Nice way to reduce the reliability or life of your device's battery.

What? No. The cable charges at 1A on a PC. A regular Lightning cable on a sufficiently powerful charging block can do 1A easily. It's nothing these devices aren't already designed for.

Many devices (especially tablets) charge at even higher amps. 2+ amps is not uncommon. But really the devices are smart enough to draw what they need... heck even having a higher amp source doesn't necessarily mean it will charge "too fast".
 

burkhartmj

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Aug 31, 2012
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I'm pretty sure 500ma is the electrical limit of USB2, how can they circumvent the standard, and why would data have any impact on that.
 
Some important things here.

1. Many computers will allow more than 500ma from a USB port. This is upto the board maker(some allow more on the back ports as well). I have boards that cut out at exactly 500ma and others that will let me pull 2 amps without issues.

2. A device can NOT be damaged from a high current plug. Higher voltage, yes. Current? no. It will only take what it needs.

I would guess this switch simply lies to the device telling it that it has a dedicated charger and not a computer. This would also explain why data transfers shut off. The device(phone/tablet/ect) most likely limits the charge rate when attached to a computer to adhere to the USB standards.
 

InvalidError

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Not really.

The battery charge controller is built into your phone/tablet/whatever so it does not matter how much current or power the cable can provide by whatever means that might be since your device will never draw more current than it needs. If your device is only designed for 500mA charging rate, it will current-limit itself to 500mA regardless of what the fancy cable can provide.

Most modern devices though ship with 1.4-2A wall adapters, so even 1A is still short from the peak charging rate they are designed to handle. In many cases, voltage drop across the cable and connectors will force devices to throttle their charging rate back a few notches too.
 

elcentral

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its like some people already stated previously. the device will try to take the ampere it needs and it will not be able to go beyond it. if you know ohms law you will understand that if you got 12V out usb and your electronics for example got 24ohm resistance U=I*R we got U=12V out on usb, we got "R=24Ohm example of a device u plug in to the usb" and you like to know how much I=ampere your unit will try to use. so now I=U/R so in this example we get 12V/24Ohm=0,5A or 500mA so in this case this cable would do nothing. the device will not use more A unless you change the Device resistance or the volt on the usb. but if the device would be at 12Ohm we would get 1A and could possible get more Watt in to the device as it will try to take 1A on the 12 volt usb. but ceep in mind 500mA is a rated Ampere not a law your mother board might let you use lots more. for example almost all 4G sticks use 800-1,000mA of your usb and they work fine so it might work.
sorry for boring you all : ) but i to got stuck in the Ampere to usb questions once.
 

elcentral

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well i actually forgot to mention this, it can help your device allot if you are the type of person using your phone while it charges. then it will need additional power not only to charge your batteries but also to power your device. i remember we used i-pads on a job once and they came with dirt cheap charges on 500mA and if you used the devise it would actually use up the battery at the same time it used the wall charger so 7 hours in it would die plugged in to the wall from low batterie. so if you cant stop playing games this might help you. or you get a good wall charger and don't need to worry. i still got my old Asus usb charger i believe the beast got like 2-3A it needed to charge 1 phone, 1 screen, 1 keyboard, all with its own batteries on 1 usb. its a good charger .
 

InvalidError

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USB operates on 5V (unless you count the new high voltage spec which nothing uses yet) and high-power USB gadgets generally use switching power supplies so their input impedance is under 1 ohm. What limits maximum input current is the PWM controller's current limit.
 

InvalidError

Titan
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The USB3 specification bumps the basic port current limit to 900mA. This still does not explain where the cable gets its 1A rating from.

Also, many devices will roll back their current when the USB voltage starts dipping from cable losses. If you start from 5V at the USB-A connector without some form of boost converter to bump voltage above 5V at the micro-B plug, devices may end up seeing only 4.8-4.9V and refuse to go beyond their lower input current capability. That's why many high-current USB power adapters have a nominal output of 5.1-5.2V to compensate for cable losses.
 

weilin

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I don't think the actual concern is the the physics itself. The bigger concern is something non-standard potentially not working on all USB hosts. A cable like this is essentially removing the "universal" from the USB.

Sure some manufacturers will design power delivery on the board to support 1A on the USB 5v rail. However, that's not part of the USB spec and it's very possible that many manufacturers won't be that cautious. In fact, I would assume that most Manufacturers never thought of it and never really designed with that constraint, if the board happens to give 1A off USB 5V, it was an accident...

There are specially designed USB ports that DO support 1Amp, and manufacturers usually denote them with a special color (Red I think?). Those are the exception and not the rule.

If you try pulling too much current, the voltage starts dropping on the USB 5V rail. This may cause undefined behavior in other USB devices (and other things that uses the USB 5V rail). This can compromise system stability.

Some boards have over-current protection and shut the system down... Others will just let 5V droop until stability is compromised and the computer crashes. If traces are done really poorly, the extra heat from 1A could burn out traces on the board. (remember, USB is found on all sorts of "computing" devices, including stuff that costs a few bucks to make. As long as the device supports USB protocols, it can give the device 500ma)
 
No way device makers are accidentally allowing more current. It is a choice. The standard even called for reduced power until the device established its power needs.

A simple resettable fuse(not sure if a polyfuse would work) or current limiter is what most boards do use to cut off use of excess current.

Many makers outright advertise usb charging as a feature(they have for years). It would take lots of power to drop the usb port voltage enough to cause issues(its not like the traces are that thin on a board) with the system(a short could cause issues, but USB ports tend to be protected against this type of thing).
 

weilin

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USB is implemented on many systems. They're all USB 2.0 compliant (and support low current and high current mode) but is designed under the assumption that the device will never ask for more than 500ma. A cable like this can very much compromise the stability of those systems.

I think you're limiting the discussion to relatively mid/high performance platforms. The vast majority of computing devices sold are much simpler than the computers you're thinking of. Also, not every board is made by ASUS/GIGABYTE/FOXCONN et al. There are plenty of knock-off/no-name boards sold in Asia that make Acer seem reliable. Those type of "computers" come with a bare minimal power supply, where the 5v on the USB is directly tied to going to the power subsystem that goes to the CPU. Something like this can easily over tax the system.

For devices like those, having a fuse/breaker/over-current protection is too big of a cost. These devices are made as cheaply as possible. However, due to whatever requirement, support enough of the USB protocol to grant high current (500ma).

A theoretical example off hand would be something like Raspberry Pi. (Please note that I don't actually know if the Raspberry Pi has over-current protection, this is targeted more towards that family of products.) It has a full USB controller which can grant this custom cable 500ma however, that means both the Pi and your phone will now try to pull from the wall outlet which probably can't handle the 2A that both devices will need. You will take the system down, and potentially fry the Raspberry Pi power supply and possibly fry a few controllers too.
 

InvalidError

Titan
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You do not need to support the USB protocol at all to get 500mA out of it. Take a USB cable, chop off the B-end, connect a load across +5V and GND, then away you go. On my Asus P5Q, I could pull about 700mA from USB2 ports before power to the port got cut off.

Supporting the USB spec enough to declare power usage is only a nicety - let the hub know how much power your port might draw so the PC can manage declared hub power accordingly if necessary. While devices are technically not supposed to draw maximum power before telling the PC how much power it will draw, most PC host port implementations do not enforce it.

The new USB3 high-power spec (up to 5A @ 20V) does require USB communication to enable since the port power management only provides 900mA @ 5V by default for backwards compatibility.
 

weilin

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But your board does enforce it, It lets you go up to 700ma (the tolerance above 500ma is to, among many things, account for peak current). When you tried to pull more it gets cut off. I'm actually surprised it let you go that high (because it's technically supposed to negotiate for high-current mode). Since it's a desktop, I can understand why that extra circuitry is foregone. I'm not really concerned with devices like yours. the worst thing that could happen is the port is shut off. You may have to restart your computer to get that port working again but that's about it.

There are many devices that don't have that current protection. If you asked for 1A or 10A it will happily try give it to you, at least for a short amount of time. Up until the power source fails. My example is still the Raspberry Pi like device or a really crappy 3rd party controller (something much worse than what VIA/AsMedia/TI etc makes, I'm not worried about the USB2 ports found in Intel/AMD chipsets, they all got over-current protection) added to a no-name board. I can see this cable causing problems for devices like those.
 

InvalidError

Titan
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I was talking about the part of the USB spec where devices are supposed to stay in low-power standby mode (few mA) until they have requested high-current (up to whatever the port's limit is) and got OK'd by the host. It is in the spec but practically never enforced - you can draw up to the port's 500-2000mA current limit without talking USB at all.



The USB current limit on motherboards is usually provided by discrete current limit ICs in SOT23, SOIC8 or similar packages. If your cheap host forgoes those chips on their USB port, then whatever gets plugged into those ports could potentially draw whatever current it wants up to whatever might cause something to fail or whatever the client device's own current limit is regardless of what cable you use.
 
Just to make the USB spec more complicated, to get that 5A at 20V the cable itself has to declare its carrying capacity. The host is not supposed to provide that much power unless the cable indicates that it can carry the load. "Requires new detectable Cables for > 1.5A or > 5V," it says, but I'm starting to suspect that at least 5V at 2A will be provided without detectable cables even by a charger that does know about profiles. I've got a charger that will go to 12V with a 12V device, but it also lets my 5V 2A devices charge. Many power sources do, indeed, work out-of-spec. But it's a crapshoot when you depend on that.

I remember reading about cables using a small capacitor to indicate that they are capable of handling the higher profiles, but I can't find the reference. Anybody know either way?
 
Yeah lots of different setups from voltage dividers to the data pins from power lines to capacitors to request charging or to tell a device your port is good for so much current.

Some devices it was as simple as shorting out the DATA lines.

This 20 volts looks very interesting because more power over the same size cable will be possible. I would also like to see the DC-DC converter used for this(12 -> 20 at over 90% efficiency to avoid too much waste).
 
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