Travel and USB Electronics
Universal Serial Bus (USB) electronics have changed how we travel. These devices are small, lightweight, and work internationally. This is why traveling with USB is one of the Five Key Principles of Light Travel. An increasing number of electronics charge and communicate via USB, making it even easier to take electronics on the road. Unfortunately, many people don’t fully understand how USB really works. Since they don’t understand USB they are travelling with more equipment (and more weight) than needed. Today we’ll look at how the majority of USB powered devices work and show you how to travel lighter with them.
Many electronic devices have a USB charge option
When most people think USB they think of smart phones, MP3 players, battery packs, and GPS devices. But wait, there’s more! Manufacturers have expanded the choices to include personal computers, headlamps, batteries, mobile Wi-Fi (MiFi), and portable shavers. Almost any low power device is now available with a USB charge option. Consider looking for a smaller and lighter USB version of your electronics the next time you shop for a new or replacement item.
All USB chargers convert incoming voltage to 5 volts direct current (DC)
All USB chargers are known as “step-down” converters and drop the output voltage to 5 volts – regardless of the input voltage. So why do you really care about this? It means that the charger will convert any standard input voltage to the correct output voltage. You can use a USB charger on all continents without using a voltage converter. All you need is a country specific adapter plug. You can also use the 12 volt power port in your automobile. Your USB power device is happy and fine with it.
USB electronics have multiple charging options
USB devices are low power direct current (DC) devices. This means that they have many charging options that are not available for higher power alternating current (AC) devices. USB devices charge through solar cells, USB auto power plugs, USB wall chargers, computer USB ports, and hand crank batteries. The odds are that you will find at least one of these options available during your travel. The solar charging and hand crank options also make USB devices great for emergency situations. It may take a while to charge the device, but at least you will eventually charge it!
Most newer USB devices – except for Apple – use micro-USB connectors
Several manufacturers met in 2007 to standardize mobile phones. This means that most phones manufactured after 2007 use micro-USB connector/synch cords. Other electronics groups started using this standard too. The only major exception is Apple, which uses the Lightning protocol. Why do you care? It means that all of your non-Apple devices can share the same connector cord. Rumor has it that Apple will be forced to use to the new standard by 2017. Apple does provide a micro-USB to Lightning adapter if you only want to use a micro-USB connector cord. I have had mixed success using the adapter. I have never had problems charging my iPhone but have had multiple problems synching with iTunes. I finally gave up and decided to carry an extra Lightning connector cord when I travel. That means I bring 2 cords – an Apple connector for my iPhone and a micro-USB connector for everything else.
USB devices come in 0.5 Amp, 1 Amp, and 2 Amp versions
Most of the older (pre 2007) and smaller USB devices take 0.5 A as the input current. Smart phones take 1 A as the input current. Larger devices, such as Kindle, iPad, PCs, and tablets need a 1.8 - 2 A input current. This means that you can’t use a 1 A smart phone charger to charge your 2 A iPad as it doesn’t have enough current. But here’s something you should know - the same 2007 standards that directed that USB devices use micro-USB connectors also directed that USB electronics automatically limit current so they won’t blow up. That means you can use your 2 A iPad/Kindle charger to charge your 1 A smart phone. That’s right – a single 2 A charger will charge all your devices! If you want to charge two devices at once then buy a 2 port USB charger that outputs 1 A on one port and 2.1 A on the other port. This will take care of all your charging needs.
Warning #1 - some multi-port USB chargers list their amperage as a combined amperage. The spec will say something like “2.1 A combined”. This means that the total output is 2.1 A. If you plug a 2 A device into one port then there is nothing left over for the other port. If you want a true dual port charger that charges two devices at once it will have a 3 A total rating. (1 A + 2 A). Read the specification before you buy!
Warning #2 - Older automobile power ports are not equipped for the higher current dual port chargers, although true cigarette lighters do have enough current. You will blow the auto’s fuse if you try to charge a 1 A device and a 2 A device at the same time in a low power port (you’ll know when it goes dead). Keep your charge current below 2 A in an older auto (one iPad or 2 smartphones). Even some newer autos only output 1 A, which isn’t enough for a tablet device. It will charge very slowly, if at all. Autos are slowly switching to higher power outputs but it is a bit of a gamble, especially with rental cars.
My Personal Solution
I travel with an iPhone and several standard USB devices. Sometimes my travel companions use a higher power iPad. My solution is to bring a dual port USB wall charger. One side charges at 1 A, and the other side charges at 2.1 A. That means that I can accommodate any type of USB electronics. I have a dual port auto charger configured the same way. I can charge two items at the same time using the wall plug - I just need two connector cords.
Because I have an Apple device, I bring two different types of connector cords. One cord is a micro-USB cord and the other is an Apple Lightning cord. My Lightning cord is 4 feet long (1.2 m). The longer cord lets me use my smart phone while it is charging. It also reaches the auto power port when I have my phone mounted on the car as a GPS device. If I did not own any Apple products I would bring two micro-USB connectors.
I bring a USB powered head lamp and a USB powered battery charger in addition to my synch cords, auto, and wall chargers. My electronics fit into a small zip-loc.
Travel lighter – dump the chargers!
Take some time to go through your travel electronics. See if you can combine chargers and cords. Consider ordering a multi-port USB plug so you can combine chargers even more. Dual port chargers eliminate fights over the wall plug/auto power port. They are also great when all the wall plugs are in use. You can almost always negotiate sharing the plug with another user if you have a dual port plug. That feature alone is worth the investment!
Updated on July 7 2014 – Added warning about dual port USB chargers in response to a question from Facebook.