A Look Inside

Before reading this page we strongly suggest to take a look at this article, which will help you understand the internal components of a PSU much better.


The OEM of the STR-500 is Super Flower which also sells the same platform to the retail market under its own name Golden Silent, which sounds a bit strange given that this is a platinum unit. The top heatsink is in close contact with the two large primary and secondary heatsinks via two enormous heatpads. The task of removing the top heatsink is not so easy since we had to deal with six long screws and the sticky heatpads afterwards.


Similar to the LZP-550 on the AC receptacle we don't find any components of the transient filtering stage. Also in the first of the above photos you will notice several heatpads on the casing which as it seems plays also the role of a big heatsink. We have already seen this technique used in Seasonic X series PSUs.
All components of the transient filtering stage reside on the main PCB: two coils, three X and four Y caps. Unfortunately there is no MOV present and that's a big shame. In such a top performing platform we can't understand why Super Flower chose not to install a MOV, the components that protects the PSU (and the whole system) from spikes coming from the power grid.


The bridge rectifier is sandwiched among two heatsinks. Afterwards, in the APFC, we find a lonely IPW50R140CP mosfet and a boost diode (C3D10060). The smoothing capacitor is wrapped in heatshrink but we recognized its brand, Nippon Chemi-Con. Between this capacitor and the resonant inductor there is a thermistor for inrush current protection and a relay to bypass it once the PSU starts. The main switchers are two IPP50R199CP mosfets and an LLC-resonant converter is utilized to give an efficiency boost.


Right next to the resonant inductor we find a vertical PCB that holds the PFC controller, an NCP1653A.


Between the primary and the secondary heatsink we find a resonant inductor and the main transformer. Super Flower didn't use an integrated transformer, instead preferred the use of two separate ones. In front of the resonant inductor, soldered to the main PCB, resides the standby PWM controller, an ICE3B0565.


In the secondary +12V is generated by four IPP023N04N mosfets and the minor rails are generated by two DC-DC converters. We find lots of polymer caps here and some electrolytics. All are provided by Nippon Chemi-Con. In the secondary, on a vertical daughter-board, an SF29601 LLC resonant controller is housed. This controller is a Super Flower's propriety design so no information is available on the net. For sure besides the primary switches it also handles the unit's protections since there is no other housekeeping IC present.


The same platform can deliver up to 800W.


Up to five +12V rails are supported by the main PCB but in this case only three are used and these are shorted together to form a single rail.


On the modular PCB we find two small Nippon caps for some extra current ripple filtering. Soldering on the modular PCB is quite good.


Soldering quality on the main PCB is decent, although we have seen much better.


Since there is no fan we shot some photos of the huge heatsink.