A Look Inside & Component Analysis

Before reading this page, we strongly suggest a look at this article, which will help you understand the internal components of a PSU much better. Our main tool for the disassembly of the PSU is a Thermaltronics TMT-9000S soldering and rework station. It is of extreme quality and is equipped with a matching de-soldering gun. With such equipment in hand, breaking apart every PSU is like a walk in the park!


The PSU is made by Sirtec and the platform is outdated and costs very little since Silverstone and Sirtec meant to keep the unit's final price as low as possible. We came across this platform in our OCZ Fatal1ty 550 W review. The main PCB is small and the heatsinks are tall and have long fins; however, every heatsink except for the one in the secondary side is thin. The major rails are generated in a group regulation scheme, so we don't expect much in terms of performance, especially in our crossload tests. Also, a passive design is used in the secondary side, which will influence efficiency negatively at especially higher loads, and the PCB is single-sided, a common solution in budget PSUs.


The transient filter starts at the AC receptacle with a single X and two Y caps, and we were surprised to find a CMD02X on the X cap. This specific IC restricts energy losses on the bleeding resistor which allows X caps to be discharged extremely quickly. The same filter continues on the main PCB with two CM chokes, a pair of Y caps, and a single X cap.


The single bridge rectifier is cooled by a dedicated heatsink, and the small MOV is installed right in front of it.


In the APFC converter, two AP20S60I fets and a single BYC10-600 boost diode are used. The bulk cap is provided by Su'scon (330 µF, 400 V, 85C, LX series) and is of very low quality and low capacity. The prerogative was obviously to save a couple bucks by using the most affordable cap around.


Two Magnachip MDP18N50 fets are used as main switchers. The same heatsink that holds the above fets also hosts the SBR that rectifies the 5VSB rail, a UTC 2N60L.


A group regulation scheme where the +12V and 5V rails are regulated by the same circuit and the 3.3V rail by another is utilized in the secondary side. The only two chokes here are a clear indication of this and the main disadvantage of group regulation over independent regulation as every rail's performance will be fairly mediocre whenever the loads are not distributed evenly across all rails.


Four PFR30L60CT SBRs (Schottky Barrier Diodes) rectify the +12V rail, while the minor rails are generated by two Mospec S30D45C SBRs. All filtering caps in the secondary side are provided by Su'scon - definitely not the best choice for even a budget PSU.


The protections IC, a Sitronix ST95313, is soldered directly to the main PCB, and we didn't find any information about it on the Internet. Judging by its size and the unit's specifications, it must only provide the very basic protection features.


Soldering quality on the rear side of the main PCB is good enough for a PSU with such a low price tag.


We found a CM6803 IC, the combo PFC/Standby controller, and a CM03X Green PFC controller on the solder side of the PCB.


The fan is provided by Globe Fan, and its model number is S1202512L (120mm, 12 V, 0.18 A, 2000 RPM, 67.28 CFM). It uses a sleeve bearing since a ball-bearing fan is out of the question because of the PSU's low price tag, and it is fairly quiet while operating under normal conditions, but the PSU's fan profile is also rather aggressive, so the ST60F-ESB is not a quiet PSU.