How does it draw the exact current it needs? Is it as simple as that because my headphones just have resistance of 5 ohm?
And also, my 5V2A charger can charge any 5V devices that draw current equal to or below 2A right?
In: 0
What we call chargers are actually voltage sources. This means that the little thing you stick in the wall outputs a specific voltage +/- a small amount. The device connected to it will draw whatever current it draws. A well designed power supply will limit the output current so that its electronics are not damaged and will not start a fire.
The amperage rating on a voltage source just means that it will limit the output current to that current. On a poorly designed voltage source that 2A may just be a suggestion, and trying to pull more than 2A can cause the charger to be damaged or catch fire.
Since most consumer devices are designed for use with voltage sources, as long as the voltage matches and the required current is less than the stated amperage you are good to go. There are exceptions to this, though they are quite rare.
Latest Answers