FSP Raider 650 W Power Supply Review

Primary Analysis

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

This power supply uses one GBU1506 rectifying bridge, which is attached to an individual heatsink. This bridge supports up to 15 A at 100° C. So, in theory, you would be able to pull up to 1,725 W from a 115 V power grid. Assuming 80% efficiency, this bridge would allow this unit to deliver up to 1,380 W without burning itself out. Of course, we are only talking about this particular component. The real limit will depend on all the components combined in this power supply.

Figure 11: Rectifying bridge

The active PFC circuit uses two JCS18N50FH MOSFETs, each supporting up to 18 A at
25° C or 11 A at 100° C in continuous mode (see the difference temperature makes) or 72 A at 25° C in pulse mode. These transistors present a maximum 270 mΩ resistance when turned on, a characteristic called RDS(on). The lower the number the better, meaning that the transistor will waste less power, and the power supply will have a higher efficiency.

The output of the active PFC circuit is filtered by one 330 µF x 420 V electrolytic capacitor, from Teapo, labeled at 85° C.

Figure 12: Capacitor

In the switching section, this power supply uses the same configuration as FSP’s Aurum Gold units, called active clamp reset forward. The switching transistor is an SPA17N80C3 MOSFET, which supports up to 17 A at 25° C or 11 A at 100° C in continuous mode, or up to 51 A at 25° C in pulse mode, with a maximum RDS(on) of 290 mΩ. A second transistor (resetting transistor) is used to turn off the switching transistor and is controlled from the secondary side. The transistor used for this function is an FQPF3N80C.

Figure 13: Switching transistor, resetting transistor, active PFC diode, and active PFC transistors

The primary is managed by a custom-made active PFC/PWM controller called FSP6600D. Since this is a custom integrated circuit, no datasheet is available for it.

Figure 14: Active PFC/PWM controller

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