Gigabyte Odin Plus 700 W Power Supply Review

Primary Analysis

On this page we will take an in-depth look at the primary stage of Gigabyte Odin Plus 700 W. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.

This power supply uses two GBU806 rectifying bridges connected in parallel and attached to an independent heatsink. Each bridge can handle up to 8 A at 100° C allowing this unit to pull up to 1,840 W from a 115 V power grid without burning themselves; assuming 80% efficiency, they would allow this unit to deliver up to 1,472 W without burning themselves out. Of course we are only talking about this component and the real limit will depend on all other components from the power supply.

Figure 9: Rectifying bridges.

Two FCP16N60 power MOSFETs are used on the active PFC circuit, each one capable of delivering up to 16 A at 25° C or 10.1 A at 100° C in continuous mode (note the difference temperature makes) or up to 48 A at 25° C in pulse mode. These transistors present a maximum resistance of 220 mΩ when turned on, a characteristic called RDS(on). This number indicates the amount of power that is wasted, so the lower this number the better, as less power will be wasted thus increasing efficiency.

This po
wer supply uses two electrolytic capacitors to filter the output from the active PFC circuit. The use of more than one capacitor here has absolute nothing to do with the “quality” of the power supply, as laypersons may assume (including people without the proper background in electronics doing power supply reviews around the web). Instead of using one big capacitor, manufacturers may choose to use two or more smaller components that will give the same total capacitance, in order to better accommodate space on the printed circuit board, as two or more capacitors with small capacitance are physically smaller than one capacitor with the same total capacitance. Gigabyte Odin Plus 700 W uses one 330 µF x 400 V and one 270 µF x 400 V capacitors in parallel; this is equivalent to one 600 µF x 400 V capacitor. These capacitors are Japanese, from Chemi-Con and labeled at 85° C.

On the switching section Gigabyte Odin Plus 700 W uses another two FCP16N60 transistors, as you can see in Figure 10. The specs from these components were already published above.

Figure 10: Switching transistors, active PFC diode and one of the active PFC transistors.

The switching transistors are controlled by a FAN4800 PWM controller.

Figure 11: PWM controller.

Now let’s take a look at the secondary of this power supply.