Aerocool V12XT-600 Power Supply Review

Secondary Analysis

This power supply has five Schottky rectifiers attached to the 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 is generated using two SBR40U60CT Schottky rectifiers connected in parallel, each one having current limit of 40 A (20 A per internal diode at 100° C, 0.57 V maximum voltage drop). This gives us a maximum theoretical current of 57 A or 686 W for the +12 V output.

The +5 V output is generated using one SBR30A40CT Schottky rectifier, which is able to handle up to 30 A (15 A per internal diode at 110° C, 0.50 V maximum voltage drop). This gives us a maximum theoretical current of 21 A or 107 W for the +5 V output.

The +3.3 V output is generated using another two SBR30A40CT Schottky rectifiers connected in parallel. This gives us a maximum theoretical current of 43 A or 141 W for the +3.3 V output.

Of course these are all theoretical figures. The real current limits will depend on other components, especially on the coil used.

Figure 14: +3.3 V, +5 V and +12 V rectifiers

The outputs are monitored by a WT7525 integrated circuit. This circuit supports over voltage (OVP), under voltage (UVP), and over current (OCP) protections. This circuit offers four over current protection channels (one for +3.3 V, one for +5 V, and two for +12 V), correctly matching the number of +12 V rails advertised by the manufacturer (two).

Figure 15: Monitoring circuit

The electrolytic capacitors available in the secondary are from Teapo and labeled at 105° C.