4 ms·

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)?

caseysoftware 10y ago
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.
- labster 10y ago
  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.
Animats 10y ago
Yes. They're called "Charge Only Hardware Firewalls", and they are way overpriced.[1] [1] https://lockedusb.com/ https://lockedusb.com/
- johannes1234321 10y ago
  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.
  - wtn 10y ago
    The non-Apple protocol is Qualcomm Quick Charge: https://www.qualcomm.com/products/snapdragon/quick-charge https://www.qualcomm.com/products/snapdragon/quick-charge
    - johannes1234321 10y ago
      Thanks!
mattzito 10y ago
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 http://int3.cc/products/usbcondoms
frederikvs 10y ago
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.
tombrossman 10y ago
I have these and they work exactly as advertised: https://www.amazon.com/PortaPow-Specialised-20AWG-Charge-Short/dp/B00T0DW3M6/ 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.
hengheng 10y ago
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.
c22 10y ago
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.

caseysoftware 10y ago

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.

labster 10y ago
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.

Animats 10y ago

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

johannes1234321 10y ago
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.
- wtn 10y ago
  The non-Apple protocol is Qualcomm Quick Charge: https://www.qualcomm.com/products/snapdragon/quick-charge https://www.qualcomm.com/products/snapdragon/quick-charge
  - johannes1234321 10y ago
    Thanks!

mattzito 10y ago

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 http://int3.cc/products/usbcondoms

frederikvs 10y ago

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.

tombrossman 10y ago

I have these and they work exactly as advertised: https://www.amazon.com/PortaPow-Specialised-20AWG-Charge-Short/dp/B00T0DW3M6/ 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.

hengheng 10y ago

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.

c22 10y ago

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.