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Westinghouse Commits to Green Plug's Universal A.C. Adapter
Ian Lamont writes "Westinghouse is the first major electronics manufacturer that has publicly committed to using a 'smart power technology' that will let people use a single universal adapter to power their laptops, cell phones and other electronics. The universal adapters, which use a technology developed by a startup called Green Plug, will act like a hub that several devices can plug into, and will also shut off the power supply when the device is turned off or has finished charging. The first are expected to go on sale in early 2009 for under $100, according to Westinghouse's CTO. Eventually, Westinghouse and other manufacturers that use the technology could stop shipping adapters with their products, because customers may already have universal adapters at home. However, some manufacturers may not be inclined to use universal power adapters: the article notes Apple gets supplementary revenue from the sale of proprietary connectors for the iPod and other devices."
USB devices have two levels of power they can draw - one very tiny amount, and a larger amount (guess which one charging your phone requires?)
When a USB device is plugged in, it only gets the minimal amount. If it needs more, it has to negotiate for it... and operating systems do this with a driver. If you have no driver (or the amount of power requested would overload the USB bus), the request for the higher power level is denied, and the phone doesn't charge.
Generic USB chargers just accept the request, unless it's for more than they can put out... which might have caused your problem... but it's not the phone that's at fault. (The phone needs what it needs, so if the charger can't or won't supply it, there's nothing the phone can do about it.)
because they don't have a default answer in a generic USB driver. It's one of the little digs they take so that each manufacture has to write a WHQL driver so their device will "properly" talk. This is instead of simply providing the industry standard, or most common, answer to the request when made.
They pulled the same crap with the power management specs on laptops, so OEMS could "optimize" their performance, instead of simply implementing the default optimizations from the chip manufacture directly. The reason is that it keeps devices tied to Windows drivers and keeps OEMS in the Microsoft upgrade treadmill.
When did Radioshack have anything like this?
Radioshack had "universal" adaptors, that basically had several different plugs, and you could select the voltage and polarity, so you could make it work with your device.
Green Plug uses the same plug for all devices, and when you plug in a device, the device and the power supply communicate. The device tells the power supply what its power needs are, and the power supply supplies that.
pins x & 4 are shorted (actually a small resistor) at the phone end on a Moto USB charger. You can easily mod a standard one to work, there's instructions on the web. E.g. http://pinouts.ru/CellularPhones-A-N/razrv3_charger_pinout.shtml
Other similar phones use different but similar schemes.