选择正确的电源适配器

　　选择正确的电源适配器

　　电子设备是我们现代世界中经常出现的一部分，所有电子设备共享的一件事就是对电力的需求。一些电子设备是由电池供电，而另一些依靠墙壁适配器。各种设备的直流电压，可以通过使用壁适配器转换成一个给定的设备的直流电压从一个典型的壁出口成一个直流电压操作。有许多问题可以用来确定哪一个壁充电器将工作的设备。

　　选择电源适配器的一些电气考虑的电压，该设备将在操作，该设备的当前要求，以及最大输出功率，您的适配器将需要能够提供。

　　You will want to choose the exact voltage that your device is supposed to operate at. Current and power have a broader range of options when choosing your adapter. You can always go above a given requirement for current and power in an adapter， this is because the current will be a result of the given impedance of the device and voltage. Your device will draw a certain amount of current regardless of how much your adapter can supply. When thinking about output power ratings for an adapter， it is good to remember that the rating is a maximum rating. Using any power supply consistently at its maximum power output will eventually cause damage to the power supply so having an adapter that has a higher rating than you need is a good thing. Another thing to keep in mind is whether your adapter requires a positive center or a negative center. This can usually be determined by the markings on the existing adapter that will look like this：