Component Analysis

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This is a budget Seasonic platform. To save money, Seasonic didn't use a double-sided PCB, but components haven't been compromised on since Infineon and Nexperia FETs and Japanese caps are used. The only letdown is the sleeve bearing fan, but it is by Globe Fan, which is a respectable manufacturer. The heatsinks are small on both the primary and secondary sides. The design is contemporary, with a half-bridge topology and resonant converter on the primary side and synchronous rectification and DC-DC converters on the secondary side.


The transient filter is complete. There is also an MOV for protection against power surges.


I found a discharge IC in the transient filter; it provides a small efficiency boost.


An NTC thermistor lowers inrush currents. A bypass relay supports it.


The pair of bridge rectifiers can handle up to 20 A.


The APFC converter uses two Infineon FETs and a single STMicroelectronics boost diode. The bulk cap is by Chemi-Con and belongs to a good line. I would like it to have a 420 V rating, though.


The APFC controller is a Champion CM6500UNX.


The two Infineon IPP50R250CP primary switching FETs are installed in a half-bridge topology.


The resonant controller is a Champion CM6901T6X.


The main transformer is next to the parts for the LLC resonant controller.


Two Nexperia FETs regulate the +12 V rail. They are installed on the solder side of the main PCB. Two small heatsinks on the other side are used to cool them down.


The electrolytic caps on the secondary side are by Chemi-Con. There are also eleven polymer caps.


Two DC-DC converters generate the minor rails.


The standby PWM controller is an Excelliance MOS Corp EM8569C, and the 5VSB secondary rectifier is an MCC MBR1045ULPS SBR.


The supervisor controller is a Weltrend WT7527V.


Four polymer and two electrolytic caps on the modular PCB further reduce ripple. There are empty spaces for three more connectors, which are not needed for this unit.


Soldering quality is decent.


The sticker on the fan makes it clear that it uses a sleeve bearing. Seeing a PSU with a seven-year warranty using a plain sleeve-bearing fan is odd. Seasonic must be very confident about this fan's reliability.