Why All Device Wall Chargers Are Not Equal

Why All Device Wall Chargers Are Not EqualDuring a fund-raising event last year, our then 11-year-old grandson, a member of Boy Scout Troop #200, won an Apple iPod and other assorted goodies for selling the most popcorn. We all acknowledge that this was a marvelous award, but what became an issue was that he seemed to always forget to charge the device either because he had misplaced the charging unit or because he had forgotten to bring it with him. In turn, that meant that he would require the use of our Apple iPad charger, which may have already been in use, before he could get his iPod up and running again. Of course, recharging his device only took a few hours, but at times it was inconvenient for us to unplug our work device to accommodate him. So I decided to buy a second charger.

Being as frugal as I am, I then began the search for the best deal on what I needed. Upon checking into the official OEM Apple charger, I learned that the company was charging $20 or more per unit. That was a little steep for me since I knew that it would only be used when the grandson visited, so I looked for a cheaper alternative. I then found one on Amazon for $4 bucks that even included a charging USB cable. When the charger arrived, it looked like a clone of our Apple iPad charger and worked perfectly on the iPod. However, the charger was geared to work only on the iPod, which wasn’t a problem in this case since we already had a charger for the iPad.

Why wouldn’t it work on both devices? Well, the way electronics work can be equated to how water flows. The number of volts the device uses is equal to water pressure, while the device’s measure of amps represents the size of the pipes the water travels through. This means that the more amps you have, the more quickly you would fill up the metaphorical water bucket. However, when it comes to volts, too many and you could break out the bottom of that water bucket. This is a simple explanation, but it does show why different chargers will charge one device quickly while not being able to charge another one.

This concept is not new and can be evidenced back in the day when every phone manufacturer had a different connector, thus requiring that you purchase a specific charger from that company to keep your phone up and running. However, like with every new concept over the years, other accessory companies came up with generic or non-OEM connectors to break the phone company’s monopoly on accessories — some that worked and others that did not. Today, most non-Apple phones and devices are standardized and will support the use of a micro-USB connector, meaning that any micro-USB charger should work just fine with any micro-USB supported device.

Why All Device Wall Chargers Are Not EqualSo if this isn’t a problem and everything has been standardized, why do some devices take longer to charge when connected to the USB port on a computer?

I could bore the reader here with a bunch of milliamp numbers that won’t make it any easier for you to understand, but if you are interested, you can go to the manufacturer’s website to determine exactly what amperage your wall charger produces. However, it should be sufficient to say that if you plug your device into a weaker wall charger belonging to another device, it may take longer to charge. The opposite should then also hold true; if you plug your device into a wall charger with more power, it may charge faster. However, if your charger doesn’t work and you know that it has plenty of power, it could be that the issue is caused by using a different charger than the one recommended by your device manufacturer. Basically, it then comes down to whether or not the manufacturer of the unit you have chosen actually complies with the current specifications for micro-USB wall chargers.

Your next questions, given the above information — and if you have read this far — are probably, first, if you can blow up your device by using a more powerful wall charger. The answer to that question is no. Then the second question would be: Will a weaker wall charger charge a device that requires a more powerful charger? The answer to that question is uncertain: maybe, maybe not.

These are just general guidelines on charger usage and your mileage may vary because of the multitude of chargers and devices on the market. To be safe and protect your valuable electronic devices, I highly recommend that you use the proper wall charger (as designated by your user manual) and thus avoid any issues.

Comments welcome.

CC licensed Flickr photo above shared by John Federico.

Article Written by

I have been writing for Lockergnome for eight years.

  • http://www.lanarea.eu Ken Verhaegen

    Chris asked the Best one: PS Vita’s charger doesn’t even create heat. I’ve charged my iPhone, iPad, Vita (duh) for weeks with it now, and I love it! Also a usb-hub would be an awesome charger sometimes.

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  • Pearson777

    anyone know if you can use the 10W iPad charger to charge your iPhone4S as well?  Or would it be too powerful?

    • http://twitter.com/gadgetgreg Greg Gazin

      Yes you can use it. It still puts out 5V.  However, if you use an iPhone charger on and iPad it will take much longer to charge.

    • http://twitter.com/gadgetgreg Greg Gazin

      Yes you can use it. It still puts out 5V.  However, if you use an iPhone charger on and iPad it will take much longer to charge.

  • Jonathan Wakeman

    I always keep this in mind looking for wall adapters but also when I look for what USB hub to buy.

  • frozen_dude

    One other problem is that most USB power adaptors are passive, that is, it gives +5V on one pin, ground on another. Completely ignoring the Data+ and Data- pins.
    Now this is important, since many smartphones today (notably iPhone) will enter a reduced charging state, if it is unable to negotiate (using D+ and D-) a suitable amperage for the power drain, which is a GOOD thing, since that prevents the cheap USB power adaptor to catch fire, but still an annoyance since it takes more time to charge.

  • Carls

    Since these simple wall-warts are not usually switching power supplies that present constant voltage, I’d respectfully disagree with your assessment and submit that the voltage swings can be significant – deviating from +-5 vDC. Just stick a voltmeter on the leads from one of these and watch the voltage drop when you cross a resister to load the circuit. (Yes, this means you have to have a USB cable and/or a iPod cable torn apart so you can get at the leads.)