Athena Power AP-MFATX35 350 W Power Supply Review

Secondary Analysis

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. As an exercise, we can assume a duty cycle of 30 percent.

The +12 V output uses two SBL40L60CT Schottky rectifiers (40 A, 20 A per internal diode at 90°, 0.60 V maximum voltage drop), giving us a maximum theoretical current of 57 A or 686 W for this output.

The +5 V output uses one S30C45CM Schottky rectifier (30 A, 15 A per internal diode at 125° C, 0.55 V maximum voltage drop), giving us a maximum theoretical current of 21 A or 107 W for this output.

The +3.3 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 71 W for this output.

Figure 14: The +5 V and +12 V rectifiers

Figure 15: The +3.3 V rectifier

This power supply uses a PS223 monitoring integrated circuit, which supports over voltage (OVP), under voltage (UVP), over current (OCP), and over temperature (OTP) protections. This chip has four OCP 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 power supply manufacturer (two).

Figure 16: Monitoring circuit

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