Rosewill HIVE 650 W Power Supply Review

Primary Analysis

On this page we will take an in-depth look at the primary stage of the Rosewill HIVE 650 W. For a better understanding, please read our “Anatomy of Switching Power Supplies” tutorial.

This power supply uses two GBU805 rectifying bridges connected in parallel, attached to an individual heatsink. Each bridge supports up to 8 A at 100° C, so in theory, you would be able to pull up to 1,840 W from a 115 V power grid. Assuming 80% efficiency, the bridges would allow this unit to deliver up to 1,472 W without burning themselves out. Of course, we are only talking about these particular components.
The real limit will depend on all the components combined in this power supply.

Figure 10: Rectifying bridges

The active PFC circuit uses two IPW60R125CP MOSFETs, each one capable of delivering up to 25 A at 25° C or 16 A at 100° C in continuous mode (note the difference temperature makes), or up to 82 A in pulse mode at 25° C, each. These transistors present a 125 mΩ resistance when turned on, a characteristic called RDS(on). The lower this number the better, meaning that the transistors will waste less power, and the power supply will achieve a higher efficiency.

Figure 11: Active PFC diode and transistors

The output of the active PFC circuit is filtered by a 330 µF x 400 V electrolytic capacitor from Teapo and labeled at 85° C. The OCZ ZS Series 650 W uses a Japanese capacitor here.

In the switching section, two SPP20N60C3 MOSFETs are used in the traditional two-transistor forward configuration. Each transistor supports up to 20.7 A at 25° C or 13.1 A at 100° C in continuous mode, or 62.1 A at 25° C in pulse mode, with an RDS(on) of 190 mΩ.

Figure 12: Switching transistors

The primary is controlled by the popular CM6800 active PFC/PWM combo controller.  

Figure 13: Active PFC/PWM controller

Let’s now take a look at the secondary of this power supply.