Aerocool E80-600 Power Supply Review

Secondary Analysis

This power supply comes with four Schottky rectifiers attached to its secondary heatsink.

The maximum theoretical current each line can deliver is given by the formula I / (1 – D) where D is the duty cycle used and I is the maximum current supported by the rectifying diode. Just as an exercise, we can assume a typical duty cycle of 30%.

The +12 V output uses two SBR30A50CT Schottky rectifiers connected in parallel (30 A, 15 A per internal diode at 25° C, 0.55 V maximum voltage drop), giving us a maximum theoretical current of 43 A or 514 W for the +12 V output.

The +5 V output uses one STPS30L45CT Schottky rectifier (30 A, 15 A per internal diode at 135° C, 0.74 V maximum voltage drop), giving us a maximum theoretical current of 21 A or 107 W for the +5 V output.

The +3.3 V output uses another STPS30L45CT Schottky rectifier, giving us a maximum theoretical current of 21 A or 71 W for the +3.3 V output.

All these numbers are theoretical and the real current/power limits of the power supply will depend on other factors.

Figure 14: +5 V and +12 V rectifiers

Figure 15: +12 V and +3.3 V rectifiers

The secondary is monitored by a WT7525 integrated circuit. This chip over voltage protection (OVP), under voltage protection (UVP), and over current protection (OCP) with four channels (two for +12 V, one for +5 V, and one for +3.3 V). We could clearly see the presence of two current sensors (“shunts”) on the +12 V outputs, creating the two +12 V virtual rails supported by this power supply.

Figure 16: Monitoring circuit

Electrolytic capacitors of the secondary are from Teapo and labeled at 105° C, as usual.