5 ms·

Ouch. With tablets and phones being so ludicrously powered these days, I wish there was a dedicated charging standard (as opposed to hijacking a primarily data-

Ouch. With tablets and phones being so ludicrously powered these days, I wish there was a dedicated charging standard (as opposed to hijacking a primarily data-transmission standard) that supported higher power draws. It's pretty awful carrying around power bricks for portable hard drives, even though your laptop can easily supply the load if needed. Ditto phones and tablets. And maybe we can all stop using cigarette lighters as DC sources and move to something a little more sophisticated.

mitchty 15y ago
I thought http://en.wikipedia.org/wiki/USB#Charging_ports http://en.wikipedia.org/wiki/USB#Charging_ports was the plan for making usb charging aware. It looks more like all of the radios on at once is just more draw than even USB in charging mode can provide. Or do you mean we get another standard that provides even more power? I'll argue that our phones need to draw less power in their worst case modes personally.
toomuchtodo 15y ago
I think the problem is that no one is going to step forward to provide the open standard for high power/current DC power transmission for these devices. USB is amazingly ubiquitous, as is DC power in cars via the cigarette lighter adapters. Its a lot of momentum to fight against; the solution is going to need to be extremely compelling to compete against the existing USB/vehicle DC power solutions.
- cbsmith 15y ago
  I think the IEEE folks are putting their money on PoE for this. Seems like a viable choice, though to make it work for hones we'd need a standard ulti-slim connector. http://en.wikipedia.org/wiki/Power_over_Ethernet http://en.wikipedia.org/wiki/Power_over_Ethernet
  - justincormack 15y ago
    And homes would have to be wired for ethernet, which seems unlikely.
    - cbsmith 15y ago
      Newly constructed homes tend to have ethernet jacks in them. Of course, older homes is a whole different matter.
- mbell 15y ago
  It isn't about the power that can be provided, you can easily pull several amps (10-15w+) through a standard USB cable and there is already a standard for determining if your connected to a computer port or a "USB Charger" port provided by the USB group. Rather, the issue is that what is going on inside the phone. In most modern phones the input voltage is fed into a monolithic power management IC which provides the numerous voltages required to run the device, handles power on timings, and often contains the batter charger. The unit in the GN is linked below [0]. There are various ways to hook these up, but a popular method is to only supply the device power rails from the battery. If you've ever ran your phone completely dry, plugged it in tried to power it on, and watched it only start up for a couple seconds and die again, its because the battery didn't have enough charge to get through boot up, which uses a lot of power. In other words, even when your phone is plugged into the wall, its probably still running on the battery. For the same reason, most newer smart phones can't be powered on without a battery in them. Its also why a phone using a lot of power while plugged in gets very warm around the battery, you are pouring power into the battery just to remove it again, the inefficiencies in the process = heat. Thus, what it really comes down to is the ability of the phone to discharge its battery faster than it can be charged. The limit of how fast you can charge the battery can be caused by limited power (computer USB port), limits in the charger or simply by the physics of charging a li-ion without causing damage to the battery or the user. In this case, without doing the math on it, ~5W is probably about the limit of the charging IC linked below, depending on charging mode. Just a guess though, it could also be the limit of the batteries ability to charge. I have seen phones that can really switch to running on actual input power, but these seem to be less common now. It requires addition components in the form of a power switch and often a regulator. More importantly it takes board space and costs money. [0] http://www.ti.com/product/twl6030 http://www.ti.com/product/twl6030
fr0sty 15y ago
Why do we need a "more sophisticated" source of DC power? What would that even look like? 12VDC is 12VDC. Are current 120VAC (or whatever your mains voltage) similarly unsophisticated? Besides, with an install base that numbers in the hundreds of millions and most of which have well over a decade of useful life.
- rmjb 15y ago
  He's talking about using a dedicated charging port instead of using the USB port for charging. 10.5 watts (2.1 amps) at 5 volts probably wouldn't be enough to support usage while charging for the larger tablets.
- unwind 15y ago
  As far as I know, cigarette lighter connections in cars are quite "low-level"; i.e. they're not a source of clean, well-behaved 12 volt DC that you can treat like e.g. the 12 V rail of a computer's PSU. Instead, the voltage can vary depending on the state of the car's engine, the car's battery, whether or not you're currently hooking up a second battery in order to jump-start your car, and so on. It's not very sophisticated when considered as a source of 12 V DC, since it has these other parameters that are not something you'd generally expect a clean and simple power source to have.
  - bdonlan 15y ago
    This is why car chargers have a 5V regulator in them.
- Symmetry 15y ago
  Well, a firewire/1394 connection can put out 1.5 Amps at 30 Volts, for a total of 45 Watts of charging. And while those aren't as common as USB ports, you'll find them on lots of computers.
cjdavis 15y ago
IEC 62684, Interoperability specifications of common external power supply (EPS) for use with data-enabled mobile telephones, is an international standard - and is basically micro USB. Even Apple is supporting it. Some quick looking doesn't show any details of the max power rating unless you buy a copy of the spec for 45 Swiss francs.

mitchty 15y ago

I thought http://en.wikipedia.org/wiki/USB#Charging_ports http://en.wikipedia.org/wiki/USB#Charging_ports was the plan for making usb charging aware. It looks more like all of the radios on at once is just more draw than even USB in charging mode can provide. Or do you mean we get another standard that provides even more power? I'll argue that our phones need to draw less power in their worst case modes personally.

toomuchtodo 15y ago

I think the problem is that no one is going to step forward to provide the open standard for high power/current DC power transmission for these devices. USB is amazingly ubiquitous, as is DC power in cars via the cigarette lighter adapters. Its a lot of momentum to fight against; the solution is going to need to be extremely compelling to compete against the existing USB/vehicle DC power solutions.

cbsmith 15y ago
I think the IEEE folks are putting their money on PoE for this. Seems like a viable choice, though to make it work for hones we'd need a standard ulti-slim connector. http://en.wikipedia.org/wiki/Power_over_Ethernet http://en.wikipedia.org/wiki/Power_over_Ethernet
- justincormack 15y ago
  And homes would have to be wired for ethernet, which seems unlikely.
  - cbsmith 15y ago
    Newly constructed homes tend to have ethernet jacks in them. Of course, older homes is a whole different matter.
mbell 15y ago
It isn't about the power that can be provided, you can easily pull several amps (10-15w+) through a standard USB cable and there is already a standard for determining if your connected to a computer port or a "USB Charger" port provided by the USB group. Rather, the issue is that what is going on inside the phone. In most modern phones the input voltage is fed into a monolithic power management IC which provides the numerous voltages required to run the device, handles power on timings, and often contains the batter charger. The unit in the GN is linked below [0]. There are various ways to hook these up, but a popular method is to only supply the device power rails from the battery. If you've ever ran your phone completely dry, plugged it in tried to power it on, and watched it only start up for a couple seconds and die again, its because the battery didn't have enough charge to get through boot up, which uses a lot of power. In other words, even when your phone is plugged into the wall, its probably still running on the battery. For the same reason, most newer smart phones can't be powered on without a battery in them. Its also why a phone using a lot of power while plugged in gets very warm around the battery, you are pouring power into the battery just to remove it again, the inefficiencies in the process = heat. Thus, what it really comes down to is the ability of the phone to discharge its battery faster than it can be charged. The limit of how fast you can charge the battery can be caused by limited power (computer USB port), limits in the charger or simply by the physics of charging a li-ion without causing damage to the battery or the user. In this case, without doing the math on it, ~5W is probably about the limit of the charging IC linked below, depending on charging mode. Just a guess though, it could also be the limit of the batteries ability to charge. I have seen phones that can really switch to running on actual input power, but these seem to be less common now. It requires addition components in the form of a power switch and often a regulator. More importantly it takes board space and costs money. [0] http://www.ti.com/product/twl6030 http://www.ti.com/product/twl6030

fr0sty 15y ago

Why do we need a "more sophisticated" source of DC power? What would that even look like? 12VDC is 12VDC. Are current 120VAC (or whatever your mains voltage) similarly unsophisticated? Besides, with an install base that numbers in the hundreds of millions and most of which have well over a decade of useful life.

rmjb 15y ago
He's talking about using a dedicated charging port instead of using the USB port for charging. 10.5 watts (2.1 amps) at 5 volts probably wouldn't be enough to support usage while charging for the larger tablets.
unwind 15y ago
As far as I know, cigarette lighter connections in cars are quite "low-level"; i.e. they're not a source of clean, well-behaved 12 volt DC that you can treat like e.g. the 12 V rail of a computer's PSU. Instead, the voltage can vary depending on the state of the car's engine, the car's battery, whether or not you're currently hooking up a second battery in order to jump-start your car, and so on. It's not very sophisticated when considered as a source of 12 V DC, since it has these other parameters that are not something you'd generally expect a clean and simple power source to have.
- bdonlan 15y ago
  This is why car chargers have a 5V regulator in them.
Symmetry 15y ago
Well, a firewire/1394 connection can put out 1.5 Amps at 30 Volts, for a total of 45 Watts of charging. And while those aren't as common as USB ports, you'll find them on lots of computers.

cjdavis 15y ago

IEC 62684, Interoperability specifications of common external power supply (EPS) for use with data-enabled mobile telephones, is an international standard - and is basically micro USB. Even Apple is supporting it. Some quick looking doesn't show any details of the max power rating unless you buy a copy of the spec for 45 Swiss francs.