Thermaltake Toughpower 750 W (W0116RU) Power Supply

Secondary Analysis

This power supply uses four Schottky rectifiers.

The +12 V output is produced by two STPS60L45CW Schottky rectifiers connected in parallel, which can deliver up to 60 A each (30 A per internal diode, measured at 135° C). The maximum theoretical current the +12 V 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 (which in this case is made by two 30 A diodes in parallel). Just as an exercise, we can assume a typical duty cycle of 30%. This would give us a maximum theoretical current of 86 A or 1,029 W for the +12 V output. The maximum current this line can really deliver will depend on other components, in particular the coil used. This output is clearly overspec’ed.

The +5 V output is produced by one STPS40L45CW Schottky rectifier, supporting up to 40 A (20 A per internal diode, measured at 130° C). The maximum theoretical current the +5 V 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 (which in this case is made by one 20 A diode). Just as an exercise, we can assume a typical duty cycle of 30%. This would give us a maximum theoretical current of 29 A or 143 W for the +5 V output. The maximum current this line can really deliver will depend on other components, in particular the coil used.

The +3.3 V output is also produced by another STPS40L45CW Schottky rectifier. Doing the same math this output would have a maximum theoretical current of 29 A or 94 W.

Even though the +5 V line and the +3.3 V line have separated rectifiers, they share the same transformer output. So the maximum current both lines can deliver will depend a lot on the transformer.

In Figure 19, you can see the four power Schottky rectifiers used on the secondary section and also the thermal sensor located on the secondary heatsink.

Figure 19: Power rectifiers used on the secondary.

This power supply +5VSB output (a.k.a. “standby power”) uses a SBL1040CT Schottky rectifier, which can deliver up to 10 A (5 A per internal diode, measured at 95° C).