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.


The PSU is made by HEC/Compucase, like all of Cougar's units. It uses a conventional design in order to reduce production cost, since Bronze efficiency can easily be achieved by even older platforms. The secondary side uses a passive rectification design, something that we had quite some time to get acquainted with, along with a group regulation scheme for the rectification of the minor rails. We removed many parts this time around, including the bridge rectifier heatsink, the APFC cap, the main transformer, and the secondary heatsink, to provide you with a clear view and to easily identify some of the components.


Behind the AC receptacle is a small PCB housing some of the transient filtering components: a CM choke, two Y caps, and an X cap along with a discharge IC for the latter. The other components of the transient filter are on the main PCB: a CM choke, two Y caps, and a single X cap.


The single bridge rectifier is bolted onto a dedicated heatsink. Its model number is GBU1006.


In the APFC, two MDP18N50 fets chop the incoming fully rectified signal into constant pulse sequences, and a BYC10-600 boost diode takes part in the generation of the loosely regulated ~380V DC bus voltage. The single hold-up cap is provided by Panasonic (400 V, 330 μF, 105°C). It is the only Japanese cap we found.


Two MagnaChip MDP18N50s are used as main switchers. The combo PFC/PWM controller is installed on a vertical daughter-board. It is the famous CM6800TX IC made by Champion.


The main transformer of the unit was definitely not the easiest part to desolder, but it was blocking the view, so it had to go.


The 5VSB circuit is rectified by a PFR10L60CT diode and the standby PWM controller is a TNY279PN IC.


The secondary side uses passive rectification. The +12V rail and the minor ones rectify two PFR30L60CTs and four PFR30L45CT SBRs (Schottky Barrier Diodes). The presence of only two toroidal chokes means that a group regulated scheme is utilized—where the large choke is used for rectification/filtering of the +12V and 5V rails, while the smaller one is used by 3.3V. Finally, all filtering caps in the secondary side are provided by Teapo and are rated at 105°C. Teapo caps may be inferior to Japanese ones, but they are the best alternative and cost significantly less, which is why main manufacturers prefer them for their cost-effective designs.


The supervisor IC is a Weltrend WT7527V IC that supports OCP for up to two +12V rails, which matches the specifications of this unit.


Soldering quality on the main PCB is quite good. However, we found some incomplete solder joints that were in need of a little more solder on the small PCB that holds the first part of the transient filtering stage.


The cooling fan carries Cougar's logo, but its model number of (DFS122512M) easily allowed us figure out that it is made by Young Lin Tech. It uses sleeve bearings. Its other specifications are 12 V, 0.23 A, 2000 RPM, 77.7 CFM, and 32.95 dBA.