How to Choose Wall Adapters & Desktop Power Adapters
Wall adapters (wall plugs) seem simple enough, right? You plug one end into the wall and the other end into your device. What some may fail to consider are all the other options which may help save energy, time and space. When considering a wall adapter, you need to know what type of voltage your device needs: AC or DC. You should also look for a recommended charging current listed on the device you are powering. From there, decide whether you want regulated or unregulated, and linear or switching.
Finally, take a look at your device's plug socket and match it with the supply's DC output connector. The most common types of connectors are 2.1mm inner diameter x 5.5mm outer diameter female, 2.5mm inner diameter x 5.5mm outer diameter female, 3.5mm male, and even screw terminal connections (Remember to also match center positive or center negative plugs).
If your device uses a plug connector, you can find out what size plug your device needs by using some calipers and measuring the inside diameter as well the outside diameter. Traditional rulers can also be used, but keep in mind that they usually aren't very accurate and may not measure in millimeters, which is the industry standard. Adapter kits are also available which contain several common size plugs.
The "slimline"
wall adapters are also very popular because they are smaller and take up less room. If you're using a power strip, you don't want a wall adapter to take up 2 or 3 of your outlet spaces. Also take into consideration the different agency approvals. CEC approved wall adapters have the highest energy efficiency levels, which may cost more up front but save you in long-term energy costs.
Finding a wall adapter that provides enough current to your device is critical for efficient charging. Your device will draw the appropriate amount of current from the adapter, but if the adapter cannot provide enough current, the device will take longer to fully charge. Be sure to choose an adapter that is able to supply the amount of current listed on your device.
For your convenience, there are also interchangeable AC-DC regulated switching wall adapters. These adapters have AC input connectors that can be swapped for use in various countries. Plug types include: USA, European, United Kingdom, and Australian.
So next time you're searching for a wall adapter, keep in mind all of the different combinations available. Doing your research and preparation can save you any hassle in the future.
Desktop Power Supply
Table-top power supplies are very similar to wall adapters in that they both plug directly into the wall outlet and into your device. Table-top power supplies are able to provide more power than wall adapters, and also typically have a wider range of features and more agency approvals. Table-top power supplies usually have 2 components: the actual supply with a DC cord attached, and the AC power cord. Depending on which one you choose, the supply may or may not include the AC power cord.
If your supply does not include the AC power cord, there are three standard sizes that will fit on various table-top power supplies: a 2-prong Figure 8 style cord, a 3-prong standard cord, and a 3-prong Mickey Mouse style cord (comes in a flat cord or a round cord).
The most important thing to look for is what type of DC connector your device will need. Various DC output connectors include: 2.1mm inner diameter x 5.5mm outer diameter female, 2.5mm inner diameter x 5.5mm outer diameter female, 3.5mm male, 4-pin, 5-pin, and 6-pin DIN male; and also stripped and tinned wires. Once you match up the DC plug connector with your device, find the appropriate voltage and current outputs. This should be listed on the actual device.
Just like wall
adapters, it is important to provide enough current to your device for efficient charging, so be sure to choose a supply that is able to provide the amount of current needed for your device.
Desktop power supplies come in 2-prong (also 2-wire) unregulated linear, regulated linear, regulated switching, as well as 3-prong regulated linear and regulated switching configurations.