PC Power & Cooling Silencer Mk III 750 W Power Supply Review

Secondary Analysis

As one would expect in a high-efficiency power supply, the PC Power & Cooling Silencer Mk III 750 W uses a synchronous design, where the Schottky rectifiers are replaced with MOSFETs. Also, the reviewed product uses a DC-DC design in its secondary. This means that the power supply is basically a +12 V unit, with the +5 V and +3.3 V outputs produced by two smaller power supplies connected to the main +12 V rail. Both designs are used to increase efficiency.

The +12 V output uses four IPP041N04N MOSFETs, each one supporting up to 80 A at 100° C in continuous mode, or up to 400 A at 25° C in pulse mode, with a maximum RDS(on) of 4.1 mΩ.

Figure 15: The +12 V transistors

As explained, the +5 V and +3.3 V outputs are produced by two DC-DC converters, which are located on a daughterboard. Each converter is controlled by an NCP1587 integrated circuit, and each converter makes use of four IPD060N03L G transistors. Each transistor supports up to 50 A at 100° C in continuous mode and up to 350 A at 25° C in pulse mode, with a maximum RDS(on) of 6 mΩ.

Figure 16: The DC-DC converters

Figure 17: The DC-DC converters

We couldn’t find any specific integrated circuit for monitoring the outputs and implementing the proper protections.

This power supply uses Japanese electrolytic capacitors in its secondary, from Chemi-Con, labeled at 105° C, as usual.

Figure 18: Capacitors

Figure 19: Capacitors