Protection Features Evaluation

All rails have high OCP triggering points, but there is no need for this, especially for the minor rails. OPP is set high, too. On the other hand, over temperature protection is reasonably configured. Finally, there is no inrush current protection, so I measured high inrush currents with 230 V.

DC Power Sequencing

According to Intel's most recent Power Supply Design Guide (revision 1.4), the +12 V and +5 V rails must have voltages equal to or greater than the +3.3 V rail's output at all times. For our first measurement, we turn the unit off and switch it back on without a load on any of the rails.



The 3.3 V rail is always at a lower voltage than the other two rails. However, I noticed some voltage ringing at +12 V, an indication that the resonant controller has a hard time catching up in this scenario.

EMC Pre-Compliance Testing - Average and Peak EMI Detector Results

Electromagnetic Compatibility (EMC) is the ability of a device to operate properly in its environment without disrupting the proper operation of other close-by devices.

Electromagnetic Interference (EMI) stands for the electromagnetic energy a device emits, and it can cause problems in other close-by devices if too high.


I found this product's Achilles heel. Many spurs go over the respective limit, with the average and Peak EMI detectors. The EMI filtering stages need tuning to lower EMI emissions.