選擇正確的電源適配器

　　電子設(shè)備是我們現(xiàn)代世界中經(jīng)常出現(xiàn)的一部分，所有電子設(shè)備共享的一件事就是對電力的需求。一些電子設(shè)備是由電池供電，而另一些依靠墻壁適配器。各種設(shè)備的直流電壓，可以通過使用壁適配器轉(zhuǎn)換成一個給定的設(shè)備的直流電壓從一個典型的壁出口成一個直流電壓操作。有許多問題可以用來確定哪一個壁充電器將工作的設(shè)備。

　　選擇電源適配器的一些電氣考慮的電壓，該設(shè)備將在操作，該設(shè)備的當前要求，以及最大輸出功率，您的適配器將需要能夠提供。

　　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：