A Look Inside

A very first solid hint for a high quality power supply can be when having a first look at its exterior. In this case we find a nice looking enclosure, which has been well manufactured. Apart from that there is a fan from Y.L. Tech which falls into the high-end category. Removing the top of this unit we quickly see that this PSU is based on CWTs PUO platform. One can tell this by the two green transformers. Despite the fact, that this isn’t the youngest platform it can still be considered state-of-the art. The reason for that is, that the primary side features loss-less LLC conversion as well as interleaved PFC circuitry and on the secondary side we find DC-DC conversion, which has been placed on a daughter PCB.

First things first: the transient filtering stage, comes with one X and two Y capacitors right behind the AC receptacle. On the main PCB there is a pair of Y caps, another pair of X caps, two CM chokes and one MOV. The transient filtering stage is therefore very well done and complete.

Continuing we find three parallel rectifiers, which are GBU 1006 and they can be loaded with up to 30A. As we already mentioned there is an interleaved PFC circuit, which actually means that there are two APFC converter working in parallel. In the case of the APFC converters we find IPW60R099CP MOSFETs as well as a CREE C3D 10060 diode. Next to the diode there is current sensing choke. Furthermore there are two large APFC capacitors from Nippon Chemi-Con, which feature 560uF capacity at 400V and they are specified for 105°C. In order to handle the interleaved PFC circuit, there is a UCC28070 controller and behind that there is the LLC converter, which is using four SiHG30N60E MOSFETs. Still on the primary side, we find a thermistor, which has been place right next to the two main transformers. Having the thermistor here makes perfect sense, since the transformers demand cooling.

Meanwhile we’ve arrive on the secondary side and here we find a synchronous design. All MOSFETs taking care of the 12V rail are on two small and vertically mounted daughter PCBs. On each of these PCBs there are six IPD031N06L MOSFETs. Filtering on the secondary side is being handled by polymer capacitors, which has a positive effect on reliability and endurance of this unit. A SITI PS229 chip is taking care of all the protection mechanism. Furthermore there is another large daughter PCB, which hosts the connectors for the cable management. Apart from that we again find polymer capacitors from Enesol and Duratech. Furthermore there are two inductors for additional filtering and rectification. The voltage regulation chips, which generate 3.3V and 5V have been place on this daughter PCB as well, which helps reducing power losses. In total there are four M300D and four M3006D MOSFETs taking care of this job and they are controlled via an APW7159 PWM controller.

Last but not least a few words about soldering quality. Chieftecs OEM (CWT) is making sure, the soldering quality matches the overall quality of this unit, which means it’s very well done.

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Page 1 - Introduction

Page 2 - Preview

Page 3 - Delivery / Specs

Page 4 - A Look Inside

Page 5 - Result Analysis and Discussion

Page 6 - Conclusion