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Comment by fr0sty | Hacker News Reader

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.

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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.

This is why car chargers have a 5V regulator in them.

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.

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.

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