3R System iCEAGE IA450HP80 450 W Power Supply Review

Secondary Analysis

This power supply has five Schottky rectifiers on its secondary.

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 STPS20S100CT Schottky rectifiers, each one supporting up to 20 A (10 A per internal diode at 150° C, 0.71 V maximum voltage drop), giving us a maximum theoretical current of 29 A or 343 W for the +12 V output.

The +5 V output is produced by two STPS30S45CW Schottky rectifiers, each one supporting up to 30 A (15 A per internal diode at 110° C, 0.57 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 STPS30S45CW 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. 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, +12 V and +5 V rectifiers.

The outputs are monitored by a WT751002 integrated circuit, which supports only OVP (over voltage protection) and UVP (under voltage protection). Any other protection this unit may have is implemented outside this chip.

Figure 13: Monitoring integrated circuit.