As we mentioned on other articles and reviews, the first place we like to take a look when opening a power supply to have a hint about its quality is its filtering stage. The recommend components for this stage are two ferrite coils, two ceramic capacitors (Y capacitors, usually blue), one metalized polyester capacitor (X capacitor, yellow component on the pictures below) and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components than that, usually removing the MOV and the first coil.

This power supply is flawless on this stage, having one more ferrite coil, four more Y capacitors (two of them can’t be seen on Figure 9), one more X capacitor and one more MOV than necessary. On this power supply the two MOV’s are locate after the rectifying bridge and not before as is the most common location today.

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Figure 9: Transient filtering stage (part 1).

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Figure 10: Transient filtering stage (part 2).

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Figure 11: MOV’s.

Now let’s have a more detailed discussion on the components used on TOP-1100P10.