A Detailed Look
The Seasonic FOCUS+ 550W Platinum power supply enclosure is painted matte black and measures 140mm (5.5”) deep. The back panel includes an AC receptacle, Hybrid Mode switch, and main power On-Off switch. The PSU includes Seasonic’s Hybrid Silent Fan Control which allows semi fanless operation when engaged.
The high-quality Hong Hua fan (HA1225M12F-Z) is rated for 0.45A and 2050 rpm at 12 VDC. The fan incorporates a Fluid Dynamic Bearing (FDB) for long life and quiet operation.
The front panel on the FOCUS+ 550W Platinum PSU incorporates eleven modular cable connectors nicely keyed and labelled to prevent inadvertently plugging a cable into the wrong connector.
The modular cables are a combination of sleeved and flat ribbon-style with flexible insulation for easy cable routing.
Under the Hood
Here are a few pictures showing the layout and components inside the FOCUS Plus 550W Platinum power supply. Like we saw earlier with the FOCUS+ 650W Gold PSU, Seasonic is using a new platform for the FOCUS Plus series.
The PSU incorporates a full bridge LLC resonant design with DC-to-DC converters to generate the +3.3V and +5V outputs from the +12V supply. The layout of components is very clean and the soldering appears to be excellent as we would expect from Seasonic. All of the capacitors are high quality including the aluminum electrolytic solid polymer caps. For example, the primary bulk capacitor is made by Nippon Chemi-Con and is rated for 390uf, 400V and 105°C.