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 OEM of this unit is HEC: the same company that makes Cougar units. The platform is modern and utilizes an LLC resonant converter on the primary side and synchronous rectification along with DC-DC converters for the generation of the minor rails on the secondary side. To provide you with a clearer view, we removed the APFC choke, an easy task for our Hakko 808 desoldering gun.


As usual, the transient filtering stage starts right at the AC receptacle and consists of, in this case, two Y caps, a single X one, and a CM choke. All aforementioned components are installed on a small PCB. The second part of the transient filter is located on the main PCB and includes two CM chokes, a single X cap, and a pair of Y caps along with an MOV (Metal Oxide Varistor), which completes the transient filtering stage.


Two parallel GBU806 bridges rectify the incoming AC signal. They are cooled by a small dedicated heatsink.


The APFC circuit utilizes three MagnaChip MDF18N50 fets and a single BYC15-600 boost diode. The hold-up cap is provided by Teapo (400V, 470μF, 85°C, LH series) and the PFC controller is a CM6502 IC located on the solder side of the main PCB.


The thermistor that protects against large inrush currents is located right in front of the APFC cap. Next to it resides an electromagnetic relay that cuts it off the circuit once the hold-up cap is fully charged.


The main switchers are two Infineon SPP20N60C3 fets. They are backed up by a resonant converter, which allows for loss less switching. This provides a noticeable efficiency boost.


The LLC resonant controller is a Champion CM6901 and is installed on a small daughter-board.


The +12V rails is rectified by four fets (M6020AP) and the VRMs that generate the minor rails are installed on equally numbered daughter-boards. Each VRM exploits an APW7073 PWM controller along with three fets. Finally, the secondary side heatsink is reinforced by a smaller one that is installed right on top of it. It is kept in place with two screws.


All the filtering caps on the secondary side are provided by Teapo and are rated at up to 105°C. We also found some polymer ones made by the same manufacturer.


Housekeeping duties are handled by a Weltrend WT7527 IC that supports OCP for up to two +12V rails, which matches the specifications of this platform.


The standby PWM controller is a TNY280PN IC: the flagship of the TinySwitch-III series. The diode that rectifies the 5VSB rail is a PFR10L60CT.


The modular PCB is equipped with two electrolytic Teapo caps at the front and two polymer ones at the rear for extra ripple suppression. Especially the latter clearly look like a last minute job, but they are very welcome since they greatly assist in ripple filtering.


Looking at the modular PCB feels great since its soldering quality is very good. All component leads are, on top of that, short enough to avoid causing trouble.


The cooling fan is made by Young Lin Tech and its model number is DFS132512H (12 V, 0.25 A, 3 W, 1700 RPM, 91.16 CFM, 36.28 dBA). It is a middle to high speed fan that is driven by a relaxed fan speed controller. Finally, it exploits an improved version of sleeved bearing called hysint. Hysint increases a fan's lifetime, but is still not as durable as a good ball-bearing.