We were very curious to check what components were chosen for the power section of this power supply and also how they were set together, i.e., the design used. We were willing to see if the components could really deliver the power announced by Kingwin.

This power supply uses one RS605 rectifying bridge in its primary stage, which can deliver up to 6 A (rated at 75º C). This is a satisfactory rating for a 450 W power supply. The reason why is that at 115 V this unit would be able to pull up to 690 W from the power grid; assuming 80% efficiency, the bridge would allow this unit to deliver up to 552 W without burning this component. Of course we are only talking about this component and the real limit will depend on all other components from the power supply.

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Figure 7: Rectifying bridge.

On the switching section two 2SC2625 NPN power transistors are used using the half-bridge configuration. This configuration is typical on power supplies without active PFC. As you can see, the transistors used are traditional BJT transistors, not MOSFET parts. They can deliver up to 10 A continuous mode or up to 20 A in pulse mode, which is the case. Both values are given at 25º C.

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Figure 8: Switching transistors.