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Comment by Animats | Hacker News Reader

Maybe doing charging through a data connector wasn't such a good idea after all.

We need more dumb inductive charging. And no, the charger does not need a data connection.

If your phone still uses Micro-USB Type-B, I highly recommend these Monoprice cables which ground the data pins during charging:

http://www.monoprice.com/product?p_id=13166

(This makes a data USB port appear to the phone as if it's connected to a wall charger.)

Wish there was a retractable version that had both lighting and microusb...

Maybe just a stubby little syncstop[1], that you can then use with any cable?

[1]: http://www.syncstop.com/

Does the syncstop allow charging at faster than 500ma for both iOS and Android?

Random thought: couldn't one start making charging cables that only had power/ground pins present (but were still shaped like the apple/micro usb connectors)?

Yes. They're called "Charge Only Hardware Firewalls", and they are way overpriced.[1]

[1] https://lockedusb.com/

There are cheaper options than this, but mind: Those aren't completely trivial devices. They have to negotiate to get more than 100mA(?) and for that negotiation there are two protocols: Apple's and, I think, Samsung's, (which is used by everybody in the Android world nowadays) And the negotiation has to involve both, the supply and the device. Cheap devices sometimes only negotiate with the device and then draw too much electricity out of the supply, which can be damaging.

The non-Apple protocol is Qualcomm Quick Charge: https://www.qualcomm.com/products/snapdragon/quick-charge

Thanks!

People have this! You can find them sometimes as "charging" cables vs. "charge/sync" cables, or more specifically this company makes a "usb condom"

http://int3.cc/products/usbcondoms

You could do this, but you may not be able to charge as fast. By default, USB only supplies 100mA. If you want to go above that, it needs to be negotiated over the data pins I think.

I have these and they work exactly as advertised: https://www.amazon.com/PortaPow-Specialised-20AWG-Charge-Sho...

$6/each (when you buy a pair) and they do rapid charging with absolutely no data connection. There are many other branded ones that are over-priced so avoid those and try these. If you don't want the Micro USB tips you can buy the standard USB adaptor to place inline between the outlet and your existing data cable.

Dedicated charging ports exist, they can be recognized by having something like zero Ohm, or respectively 200 Ohm between D+ and D-, or 15k Ohm on each pin against ground. (See also Maxim's USB Battery Charging survival guide)

That is, "power only" cables are not recognizable to the user, and malicious chargers came into being for that reason.

I have a couple cables like this and they are the number one cause of me wondering why some stupid USB device isn't being seen by my computer. I ended up putting blue nail polish on them to remind myself.

Yes but now you're training people to trust the "safe" cables. So the first time they get a cable the think is safe, they don't even think about it, they just plug it in and go.

It's a minor annoyance not being able to sync up your own music or handle calls through the system but it's much safer. Charge off your computer or a cigarette adapter. They're always safe... as far as I know.

The cigarette adapter is much safer than the cigarette lighter, that's for sure.

Safe cables represents a much smaller attack surface than "plug into random ports" which sounds like an improvement to me.

You could even just use a small USB condom, or cable adapter. There's several retail ones, all shiny and easy to use. I keep several of these in my bag http://syncstop.com

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