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 this unit looks to be High Power/Sirfa but we are pretty sure that Thortech also made some modifications/changes to the platform. Although this is a Gold unit the primary side does not incorporate any exotic topology, neither an LLC resonant converter. In the secondary side however a synchronous design is utilized along with two DC-DC converters. The most interesting in the internals is the daughter-board that houses the 8-bit controller that supports the iPower meter. Finally, this time we desoldered the APFC heatsink, since it blocked the view.


The first part of the transient filtering stage, as usual, is housed directly on the AC receptacle. There we find one X and two Y caps. It continues of course on the main PCB with two CM chokes, one X and two Y caps and an MOV. All in all the transient filtering stage is complete.


There are two bridge rectifiers, bolted on a dedicated heatsink. This time we decided to leave them in their peace so we didn't desolder them to identify their model numbers.


After the bridge rectifiers a red wire is soldered. This one along with a black one, which is soldered nearby, most likely provides information to the 8-bit micro-controller of the iPower meter in order to calculate the efficiency percentage. Apparently they couldn't modify the already designed PCB so they had to go all the way around, in order to transfer this piece of information to the daughter-board that houses the micro-controller.


In the APFC three IPW60R125CP fets are used along with two boost diodes (CREE C3D08060). The hold up caps are provided by Nippon Chemi-Con (470µF each or 940µF combined, 400V, 105°C, KMR series). As primary choppers we find two IPW60R125CP and the combo PFC/PWM controller is a Champion CM6800AG IC. We were quite surprised to find the older CM6800 controller in a Gold efficiency unit, Thortech at least didn't choose the upgraded CM6802 for this task.


A thermistor is responsible for the protection against large inrush currents and a relay bypasses it once the start up phase of the PSU finishes.


In the secondary side synchronous design is used along with two DC-DC converters for the generation of the minor rails. The +12V rail is regulated by eight AOT480L mosfets and afterwards it feeds the two VRMs (Voltage Regulation Modules). In each VRM there is an APW7073A PWM controller and two pairs of mosfets. We were able to recognize the model numbers of the fets on only one pair (IPD060N03L) since the second pair was hidden by the secondary heatsink. Finally all filtering caps in the secondary, both electrolytic and polymers, are made in Japan and provided by Nippon Chemi-Con (except one we spotted which is made by Rubycon).


The large vertical daughter-board, shown in the photos above, houses the 8-bit micro-controller (EM78M611E) that controls the iPower meter. This controller is provided by Elan Microelectronics Corporation while the controller of the older Thunderbolt Plus 800W was made by Atmel. On the component side of the same PCB the supervisor IC is installed, a PS224, which provides OCP for up to two +12V rails and incorporates all protections except OTP.


On the modular PCB we don't find any filtering caps and this is a shame because this platform is not ripple proof, at full load at least. The solder side is completely covered by a white piece of plastic.


Soldering quality on the main PCB is quite good since we spotted very few hand made solders and all joints are nice and clear. However we've noticed some longer than usual component leads but their length doesn't fall into the dangerous zone. On the area where all +12V wires are connected to the main PCB there are four shunt resistors, indicating that this platform originally supported four +12V rails. However in this case, Thortech states that there is a single +12V rail and on top of that the supervisor IC supports OCP for only up to two +12V rails.


The cooling fan is provided by Globe Fan and its model number is RL4Z B1352512HH-3M (12V, 0.45A). It has eleven blades, uses ball bearings and there is a plastic baffle on it to direct air towards the rear side of the PSU.