iMicro PS-IM400WH Power Supply Review
Transient Filtering Stage
Contents
As we have mentioned in other articles and reviews, the first place we look when opening a power supply for a hint about its quality, is its filtering stage. The recommended components for this stage are two ferrite coils, two ceramic capacitors (Y capacitors, usually blue), one metalized polyester capacitor (X capacitor), and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components, usually removing the MOV and the first coil.
In order to cut costs, the manufacturer added only two Y capacitors in this stage. We’d like to remember you that the transient filtering stage is used not only to “clean” the electricity coming from the wall, but it is also in charge of preventing the interference created by switching section of the power supply from entering the power grid.
Figure 8: Transient filtering stage
In the next page we will have a more detailed discussion about the components used in the iMicro PS-IM400WH.