Zalman ZM600-ST Power Supply Review

Secondary Analysis

This power supply has four Schottky rectifiers on 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 is produced by two 40CPQ060 Schottky rectifiers, each one supporting up to 40 A (20 A per internal diode at 125° C, 0.68 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 produced by one STPS60L45CW Schottky rectifier, capable of delivering up to 60 A (30 A per internal diode at 135° C, 0.73 V maximum voltage drop), giving us a maximum theoretical current of 43 A or 214 W for the +5 V output.

The +3.3 V output is produced by another STPS50L45CW Schottky rectifier, giving us a maximum theoretical current of 43 A or 141 W for the +3.3 V output.

All these numbers are theoretical. The real amount of current/power each output can deliver is limited by other components, especially by the coils used on each output.

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

The outputs are monitored by a PS223 integrated circuit, which supports over voltage (OVP), under voltage (UVP), over temperature (OTP) and over current (OCP) protection (with two +12 V channels).

Figure 13: Monitoring integrated circuit.

All capacitors from the secondary are from Teapo.