Mushkin Volta 600 W Power Supply Review
Primary Analysis
Contents
On this page we will take an in-depth look at the primary stage of Mushkin Volta 600 W. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.
This power supply uses one GBU1006 rectifying bridge, which supports up to 10 A at 100° C. At 115 V this unit would be able to pull up to 1,150 W from the power grid; assuming 80% efficiency, the bridge would allow this unit to deliver up to 920 W without burning itself out. Of course we are only talking about this component and the real limit will depend on all other components from the power supply.
Two SP
A20N60C3 power MOSFET transistors are used on the active PFC circuit, each one capable of delivering up to 20.7 A at 25° C or up to 13.1 A at 100° C in continuous mode, or up to 62.1 A at 25° C in pulse mode, presenting an RDS(on) of 190 mΩ (resistance when the transistor is turned on; the lower this number the better, meaning higher efficiency).
Figure 10: Active PFC transistors and diode.
The output from the active PFC circuit is filtered by a Japanese electrolytic capacitor from Chemi-Con, labeled at 85° C.
In the switching section, another two SPA20N60C3 power MOSFET transistors are used on the traditional two-transistor forward configuration. The specs for these transistors were already published above.
Figure 11: Switching transistors.
The primary is controlled by a CM6805 PFC/PWM combo controller.
Figure 12: PFC/PWM combo controller.
Now let’s take a look at the secondary of this power supply.

