# 伺服馬達基礎實習

在使用伺服馬達之前有一點要留意的就是它的電源供應，因為馬達本身所需要的電流較大，因此大部份的伺服馬達是沒有辦法直接由micro:bit上的電源直接驅動的，在很多的情況下我們需要使用的是外部的電源。而在使用外部電源的時候，儘管馬達不是由micro:bit驅動，但是它們（馬達和micro:bit）的接地仍然要接在一起。

一般來說，我們都是在麵包板上做實驗，因此要連接使用外部電源的話，請儘量善用麵包板上的電源匯流排。也就是先把外部電源的正負電接到麵包板的匯流排上，然後也把micro:bit的GND連接到麵包板的負匯流排，如下所示：

![](/files/-LQaDSouyi5P9nAZVayF)


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