As we mentioned on other articles, 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) and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components than that, usually removing the MOV, which is essential for cutting spikes coming from the power grid, and the first coil.

This power supply uses more components than the minimum recommended: three ferrite coils, four Y capacitors, two X capacitors and one MOV (see Figure 17). As the MOV was hidden between the rectifying bridges, the PFC electrolytic capacitor and one of the ferrite coils, we took another picture from this component after we removed the electrolytic capacitors and the rectifying bridges, see Figure 18. Before the standard transient filtering stage there are two ceramic capacitors connected in series with the main AC power wires, which is unusual, as they are not using “X” or “Y” configurations (on these two configuration the capacitors are connected in parallel with the main AC power wires, not in series).

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Figure 16: Transient filtering stage (part 1).

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Figure 17: Transient filtering stage (part 2).

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Figure 18: Detail of the MOV used in this power supply.

This power supply uses a CM6800 integrated circuit, which is an active PFC and PWM controller combo. It is located on a small printed circuit board shown on Figure 19. This is the same controller used by several other power supplies, like OCZ GameXstream 700 W, Zalman ZM600-HP, Antec Neo HE 550 and Thermaltake Toughpower 750 W, just to name a few.

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Figure 19: Active PFC and PWM controller integrated circuit.

And our last remark on this preliminary look on the components found on Tagan TG1100-U95 is regarding its thermal sensor – which commands the power supply to shut down in case of an overheating situation and also changes the speed of the fans according to the power supply internal temperature. Usually this component is found attached directly to the secondary heatsink or right below it, but on this power supply it is located inside the +12 V ferrite coil, see Figure 20. This is really unsual.

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Figure 20: This power supply thermal sensor is located inside the +12 V ferrite coil.

Now let’s have a more detailed discussion regarding the components and design used on Tagan TurboJet TG1100-U95.