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 platform uses a modern design, and while its primary side uses a half-bridge topology, every Leadex unit with a higher capacity uses a full-bridge topology. All Leadex units use an LLC resonant converter with the bridge topology as it offers loss-less switching, which minimizes energy losses. The secondary side uses a synchronous design with mosfets and two DC-DC converters for the generation of the minor rails.


This time the PCB that holds the AC receptacle doesn't host any transient filter components. All of them are on the main PCB: two CM chokes, two X caps, two pairs of Y caps, and an MOV.


A single bridge rectifier is used in the 750 W Leadex.


Two Infineon IPP50R199CP fets and a C3D06060A boost diode are used by the APFC converter. The two parallel hold-up caps are located right in front of the transient filter and are by Nippon Chemi-Con (400 V, 330 µF, 105°C, KMR series).


An NTC thermistor protects the unit against large inrush currents and a close-by electromagnetic relay isolates it from the circuit once it finishes its job.


A small, sealed PCB houses the APFC controller, an NCP1653A IC.


The standby PWM controller is a Fairchild BD5AG IC.


This proprietary IC with markings AA9013 is probably the LLC resonant controller.


Two Infineon IPP50R199CP fets are used as main switches.


The secondary side has two vertical heatsinks that host four fets in total (4x IPP041N04N). Among the heatsinks are several electrolytic caps by Chemi-Con that are used for ripple-filtering purposes.


Two DC-DC converters generate the minor rails. The polymer caps on these are provided by Chemi-Con.


The 5VSB rail is rectified by a Mospec S10C60C SBR (Schottky Barrier Rectifier), and the fan control board with an LM324ADC is installed right next to it. We had to apply lots of glue to the aforementioned control board to properly secure it since accidently snapping it off its soldered base would have been very easy.


The front of the modular PCB is covered in many polymer caps and several small electrolytic caps by CapXon. It doesn't matter whether these are made in Japan or China since caps in this area are not stressed significantly. Polymer caps also last for a very long regardless of their origin.


Soldering quality is good but definitely not topnotch. However, SF is on the right track.


The fan is provided by Globe Fan, and its model number is RL4Z S1402512HH (12 V, 0.5 A, 1800 RPM, 135.74 CFM, 36.7 dBA). The same fan is used by the Rosewill Tachyon 1000 W unit, a re-badged SF PSU. The "S" nomenclature in the model number usually stands for a sleeve bearing, but the label on its centerpiece is indicative of a Fluid Dynamic bearing. Globe Fan probably used an upgraded sleeve bearing they call FDB. Finally, a small plastic baffle is attached to the fan. It funnels air toward the rear of the unit.