Contents
- 1Introduction
- 1.1Packaging and accessories
- 2Connectors & cabling
- 2.1Casing & cooling
- 3Input filtering
- 4Primary side
- 4.1+5 V stand-by rail
- 5Secondary side
- 5.1Build quality
- 6Load testing
- 6.1Loading +5 V SB
- 6.2Voltage hold-up time
- 6.3Combined loading
- 6.4Combined loading ripple
- 6.5Crossloading, overloading
- 6.6Crossloading, overloading ripple
- 7Conclusion and evaluation
- 7.1Thanks
- 7.2Discussion
Secondary side
The main transformer is quite substantial as it carries all rails, it uses 36 mm wide core. There are two transistors used for +12V rectification, it was hell to remove the module but I did it and it even worked afterwards. They are International Rectifier IRFB3206 (210/840 A at 60 V and 25 °C, Rds(On) 3 mΩ at 75 A) in TO-220 package. The whole copper heatsink is used as conductor for source pins (which are soldered to the heatsink) while one of the transistors is screwed to a copper pad which acts as parallel conductor to its drain leg. The ground is conducted through that tape-insulated metal plate visible on the image which also provides RFI shielding from +3.3/+5 V rails. Those use two Infineon IPD040N03L G (90/400 A at 30 V and 25 °C, Rds(On) 5.9 mΩ at 30 A) transistors in TO-252-3-11 package each. Custom controller labeled 6601 is used to drive the transistors, obviously there is no public datasheet for it.
A Chemi-Con PSC 470/16 polymer capacitor and custom C(r)apXon 3300/16 wet electrolytics are used for +12 V filtration while one 4700/10 and Chemi-Con KZE 3300/10 are used for +5 V. The +3.3 V rail has two more KZE 3300/10 caps. The −12V rail only has a single Chemi-Con KY 1000/16. The Weltrend WT7579 is used as secondary monitor. It is again custom IC as it has 20pin package, usually these monitors capable of monitoring UVP, OVP, OCP and OPP have 18 pins. I did not find any thermistor or other source of temperature sensing so I have no idea how this unit controls its fan. Also there is no OTP present but the box does not promise any.
Build quality
As usual I will focus on the overall build quality and other things like electrical safety here as the quality of the components used was already discussed before. FSP Group used quality double-sided fiberglass board. Many components are sleeved or extra insulated by insulation tape, I like this. There is quite enough room between components so no problem here. Primary and secondary side separation is good with several extra slots under the main transformer, optocouplers and input filtration components. Most electrodes are precisely cut or bent at least but as tens of SMD components are used, there is not many electrodes at all. 
There is some manual (re)soldering of the common secondary inductor but nearby filter has not been touched while third of it is not soldered properly…otherwise the soldering is quite clean. Paths are not so heavily reinforced with solder, I guess thanks to that (and maybe a proper cleaning for a change) I did not find many solder balls. There were two medium ones and three tiny. I think after a long series of units with terrible amounts of solders balls, this is quite OK so I’ll only take down three points for the solder balls and one point for messy soldering.
Loading ...