Codegen P-Case 460W - Low Price, Poor Qualityby Martin Kaffei on April 27, 2012 8:30 AM EST
Fan and Electronics
Xin Yu Electronics is a Chinese brand we never heard of before but "SL" tells you this fan has a sleeve bearing. Everything else with higher MTBF ratings would be too expensive. The 120mm fan needs less amps than most fans we know (0.13A) and it has seven sharp-edged fan blades. Will it be silent, and can it keep the PSU cool? We'll find out on the next page.
Basically this PSU is not far away from other solutions. We've seen many forward converters with an asynchronous half bridge but this time the components are quite cheap. The internals consist of two very small heatsinks, a small transformer, and no PFC-choke which is an important requirement for European countries. You need CE to sell power supplies in Europe and PFC is essential for any PSU with more than 75W. Instead of a bridge rectifier this PSU has four RL205 diodes which can rectify 2A RMS current. That's fine by me but bridge rectifiers in a case have the advantage that heatsinks can be used.
There are no Y- and X-caps in the EMI filtering stage, missing a MOV as well. A thermistor reduces input current--nothing special. Of course PSUs without active PFC have less EMI because of the missing MOSFET but this is kind of disappointing. Can you see the wire cross-section of the conductors? It doesn't look like anybody should try to pull more than 250W from this unit.
An IC called SD6109 delivers some safety functions such as overvoltage protection. Instead of optical coupler the manufacturer is using an isolating transformer for the feedback. On the secondary side we found one choke for all larger outputs. It gone into saturation during our test. +5 V got a large diode in a TO-247 case and is definitely the most powerful output.