USB Ports

[JGJ]

My albergue has a USB port directly above my bed for charging smartphones etc. There is no other outlet. Is this safe to use for my North American phone without having to use an adapter and wall outlet? Thanks in advance.

 

[Bradypus]

Yes. There is no need to convert the DC output from a usb charging port.

Edit: @Rick of Rick and Peg has raised an issue about the possible hacking of usb ports and the transfer of data covertly to/from your phone. His warning is in post #9 below.

 

[Bill's_Walking]

Yes it is.

 

[JGJ]

¡Perfecto!

 

[JGJ]

Yes it is.

¡Gracias!

 

[Flog]

It will work just fine. USB ports are the same the world over, one might even say they are universal.

However, there is talk of the possibility of them being hacked in public places such as airports, hotel lobbies etc so if you have a choice in such locations, go for a mains outlet. But in a small private albergue I wouldn't give it a second thought.

 

[JGJ]

Thanks so much! The last thing I needed to do was fry my mobile with less than 300 km to Santiago .

 

[Rick of Rick and Peg]

For powering your phone the USB ports will be safe but be aware that USB can connect programs also. You think you are just doing a charge but you can also be running a program on your phone that could have severe consequences.

As an example, in Barcelona in 2019 I rented a car and plugged in my phone to its USB port to charge the phone. The phone then started to deliver promotional messages for the rental company. I pulled the cord out really quickly. I didn't think the company would do anything wrong but possibly the company had been hacked. [Edit: I've since discovered other serious problems with connecting phones to rental cars. See post #22 below.]

There is a way to avoid being infected when you really only want to do a charge. There is a cheap adapter that you can insert between the phone and the USB port. It only makes a connection between the charging pins and not to the data pins. I had one and used it later on the rental car but I goofed and forgot about the danger at first. Look for USB data blocker or USB condom.

Really though, if you are already on the camino and can't get one of these adapters you have a really slim chance of getting infected at an albergue. Infection is more likely at some charging station found on the street or some transportation hub.

Edit: You could also use the USB port to charge a cheap power bank when you go out to eat and then use that to charge your phone. If someone swipes the power bank you'll be out a lot less money and external batteries can be found easily and cheaply. No problem getting viruses this way.

 

[dougfitz]

USB ports are the same the world over, one might even say they are universal.

This might seem so, but it is far from what is actually happening. There are four generations of standards with different data speeds and power delivey and a host of optional features. There are nine connecter formats if one doesn't count the Apple lightning connector which is really proprietary, although A and C connectors are the default host port connectors. What is 'clever' about the standards is that they are backwards compatible back to the USB 1.0 standards, which means that even with the oldest devices one could find, a USB port will work. While later devices are capable of delivering much higher voltages, they detect what voltage is required by the device being charged, so there is no risk of 'frying' one's phone or other device being charged.

 

[Flog]

Oh? I always assumed that all USB ports put out 5v DC, is this not the case?

 

[Flog]

They all put out 5v DC but the amount of power that can be transferred varies widely depending on the type of USB port.

Sure, but as to the OP's question and for anyone faced with the same concern: Any smartphone will charge off any USB port (albeit it will charge more slowly from a version 1.0 or 2.0).

 

[dougfitz]

Oh? I always assumed that all USB ports put out 5v DC, is this not the case?

The voltage is notional, but that is the reference point. I know that when I have tested some of my chargers under load, they deliver less than that, but not by much. I have checked the standard, but don't have the details in my head. What I do recall is that it allows for voltages below the notional 5 V reference point.

For Apple users, the 1,500 mA is generally inadequate for iPads, which need a 12W (2,400 mA) charger. Most aftermarket chargers will be able to supply that, so they are 'non-standard' to that extent.

 

[dougfitz]

Sure, but as to the OP's question and for anyone faced with the same concern: Any smartphone will charge off any USB port (albeit it will charge more slowly from a version 1.0 or 2.0).

That's quite true, and others and I have said so before when this question has been raised in various ways.

Its also the same with a multi-port charger. They will all have a limit to the overall current that can be supplied, even if the individual ports are rated at 1500 mA or 2400 mA. If you try and charge devices with a high demand, like an iPad, phone, Apple watch and Apple ear buds all at once, the charger has two options - charge everything slowly or go into overload and stop charging completely. In my family, we have travel chargers of both varieties.

 

[Flog]

The voltage is notional, but that is the reference point. I know that when I have tested some of my chargers under load, they deliver less than that, but not by much.

Yes, but the voltage will only drop marginally below this nominal 5v if you try to pull more current than it can supply, i.e, if a device 'needs' and tries to pull 800mA from a USB version 1.0 which can only supply it at 500mA, the device will charge more slowly.

For all intents and purposes, all USB ports put out 5VDC and won't damage your phone. Some of them will charge it faster than others but none will damage it.

 

[dougfitz]

For all intents and purposes, all USB ports put out 5VDC and won't damage your phone. Some of them will charge it faster than others but none will damage it.

There are two parts to this. The first part is not correct. The power delivery standards allows for voltages up to either 20 V or 48 V. However, that higher voltage may not be implemented, and it will not be delivered if you are connecting to a device that only requires 5 V. The charger can detect the device that is connected, and can adjust the voltage, and current that is being delivered, accordingly.

There will be no immediate damage to your phone from any USB charger, but in the longer term, using fast charging devices will reduce the life of your device's battery. It's a convenience with a hidden cost using such chargers.

 

[Flog]

Yes I see now from googling, you have enlightened me regarding the later generation ports, thank you:

"USB-C allows voltage and current negotiation which is handled entirely by the Host Port and peripheral device. The specification begins at 5V, 500mA, but a device can “request” up to 20V, 5A although I’ve yet to see a cable (or even a plug) that I would trust to carry this much power."


Still, to say it was incorrect is disingenuous. The USB standard is 5v and any smartphone will charge off any USB port. However it will pull whatever current it needs up to the point of what the port is capable of providing which is why as you correctly stated, a fast charger might shorten the life of a battery in the long run. The current isn't delivered as you suggested but is drawn by the device and is determined by the load presented to the power source, as per ohm's law.

Hopefully the OP happily charged his phone and is now happily discharging it taking nice photos and has long since moved on from this boring exchange.

 

[JGJ]

Thanks again everyone for your input. It’s greatly appreciated.

 

[MassNative]

I will echo the data security concern with charging on USB port. You do not know what is behind the port, if it is not your own AC-to-USB adaptor. You are opening your cell phone to potential unwanted software down loads.

You can safely charge your passive external battery on it, but you should not trust you phone on such a port.

 

[Molly Cassidy]

When I plug my phone into a device (eg laptop) to charge the a message pops up asking if I want to exchange data or just charge the phone. I presume it would be the same if someone tried to hack it.

 

[MassNative]

When I plug my phone into a device (eg laptop) to charge the a message pops up asking if I want to exchange data or just charge the phone. I presume it would be the same if someone tried to hack it.

That is what happens when you USB connect to a device that is playing by protocol rules. Hackers ignore the rules.

What is 'Juice Jacking' and Tips to Avoid It

If your battery is running low, be aware that juicing up your electronic device at free USB port charging stations, such as those found near airport gates, in hotels and other travel-friendly locations, could have unfortunate consequences.

www.fcc.gov

Jim (programmed network routers and devices for 40+ years)

 

[Rick of Rick and Peg]

Last week in post #9 above I wrote about a security problem with charging a phone with an unknown USB port. I gave an example of how my phone started to run a promotional video when I plugged it into what I thought was just a charging port. Today I learned about other dangerous things can happen.

I was browsing though YouTube for new videos and this one with the video ID of YxQbCBSKFbg came up. It has the title of Don't connect your phone to the car [rental car]. I thought I better view it after giving my advice. There was a lot of scary stuff in it that I had no idea of. Watch it, it's just four minutes long and it can save you and your friends a lot of trouble.

 

[Pathfinder075]

Loads of stuff come out each year at DefCon for hacking things via USB. The easy solution is to get a charge cable that doesn't do data or a USB condom. The other solution is to use an old phone that maybe doesn't have internet (old nokia 3210 or similar).

If DIY'ing you can cut wires 2 and 3 on a USB 1.0/2.0 cable (data wires) to achieve the same thing if you prefer that approach. On USB 3.0 it is a lot more in depth. Easier to get the dongle in that situation.

I use my own charger and would never plug a phone into a USB outlet. There is of course a work around of sorts. If you have a powerbank and it has more than one port, on some of then you can daisy chain. I've done it with a Belkin before and checked for data connection (there wasn't one), ie, plug the powerbank into the outlet and the phone into the powerbank. You sort of charge by proxy. Or you could charge the powerbank, then charge the phone and recharge the powerbank.

It also depends on a few things. If it's a burn phone purchased for the trip and not used for anything sensitive (banking, personal, etc), then it's less of an issue. But if it's your day to day phone, full of all your personal data, then being careful is being wise.

 

[JGJ]

Thanks for the update. Next time I’ll simply use my portable power pack. Silly of me not to have thought about that (senior’s moment). I’m wondering if my Norton security on my phone would have blocked any malicious stuff from the USB? I did check the Norton app and it indicated that that all was good with my phone … no issues. In any event thanks for your thorough replies. As for car rentals, I appreciate your follow up on yet another potential malicious conduit to devices. I’ve already shared your report with my family . And by the way, I’ll be in Santiago on Saturday!!!!!

 

[henrythedog]

When I plug my phone into a device (eg laptop) to charge the a message pops up asking if I want to exchange data or just charge the phone. I presume it would be the same if someone tried to hack it.

There’s a small cheap ‘plug in’ adapter referred to as a ‘USB condom’ which allows charging current through the cable but disables data. That would resolve your concern.

 

[MikeJS]

There’s a small cheap ‘plug in’ adapter referred to as a ‘USB condom’ which allows charging current through the cable but disables data. That would resolve your concern.

Or just use wireless charging.

 

[Molly Cassidy]

Or just use wireless charging.

I don't think my phone does that.

 

[trecile]

I don't think my phone does that.

Most newer phones do, but then of course you need a wireless charger, which doesn't usually charge as fast as using a charging cable and standard charger

 

[dougfitz]

Most newer phones do, but then of course you need a wireless charger, which doesn't usually charge as fast as using a charging cable and standard charger

Only half the Samsung models available in Australia have wireless charging. I am not in the market for those that do!

 

[Molly Cassidy]

I always just buy the cheapest phone I can get.