Semtech Power Supplies 101

　　在最基本的術語，降壓穩壓器需要一個輸入電壓，并將其轉換為負載所需的較低電壓。有兩種主要類型的穩壓器，線性和開關。線性穩壓器的工作原理是通過吸收輸入和輸出之間的能量差，而開關穩壓器的輸入電壓，然后平均斬波電壓，以提供適當的輸出電壓。

　　一個電壓調節器，它被放置在接近設備或設備，它是供電通常被稱為一個點的負載調節器。這種類型的穩壓器經常收到從一個包含在PCB上的電壓總線的輸入。

　　There are several parameters that should be considered when evaluating power supplies for particular applications.

　　Quiescent Current – The amount of current an IC consumes when it is not source current and its inputs are not cycling.

　　Efficiency – Defined as the ratio of power into a regulator circuit to the output power delivered by the regulator. Power input includes quiescent currents， losses due to parasitic components and power delivered to the load.

　　Equivalent Series Resistance – The resistive component of the capacitors used in a regulator circuit. Attention needs to be paid to the ESR of the capacitors of the output.

　　The Loop – Defined as all the elements affecting the output and stability of a regulator. This includes such blocks as the power stage， error amplifier， modulator， and compensation circuits.