Silver box reference design touts 92% efficiency

Infineon Technologies has developed what they claim as the first marketable silver box reference design that enables PC and server power supply units to achieve up to 92.35 percent efficiency, while significantly reducing the material costs.

Infineon's IFX90ATX300W solution is based on the latest generation of three ICs and meets the industry's highest energy efficiency standard, "80 PLUS Platinum."

Efficiency indicates what share of the power drawn is actually used. The difference between power input and power output is the power loss, which is converted into heat. Therefore, high efficiency translates into a reduction in power consumption and lowering of electricity bills.

The IFX90ATX300W contains three components and sets the benchmark for energy efficiency requirements in PC and server power supplies. The focus is on reproducibility and reliability, especially in mass production. The third generation of CCM PFC (Continuous-Conduction Mode-Power-Factor-Control) ICs—ICE3PCS01G—provides the highest efficiency available for the power range of approximately 150-500W, typical of PC power supplies accompanied by the best cost-performance ratio of the PFC stage.

Infineon's second generation of half bridge driver ICs—ICE2HS01G—contributes to optimizing the efficiency of LLC half bridge converters with synchronous rectification by optimizing the interplay between half bridge driver operation and synchronous rectification, hence preventing unnecessary switching losses.

In addition, Infineon's ICE2QR2280Z, a quasi-resonant CoolSET Current Mode Controller with digital frequency reduction, minimizes the switching losses in the auxiliary supply typically taking the form of a fly back converter, thereby achieving high efficiency especially in low load and standby mode.

"80 PLUS" is an initiative to promote the manufacture and use of energy-efficient power supplies in desktop computers and servers. For "80 PLUS" certification, power supply units have to achieve at least 80 percent energy efficiency at various load levels. In the further categories—"80 PLUS Bronze," "80 PLUS Silver," "80 PLUS Gold" and "80 PLUS Platinum"—correspondingly higher values apply. To acquire Platinum certification, a power supply has to achieve efficiency of 89 percent at 100 percent load, 92 percent at 50 percent load and 90 percent at 20 percent load. Infineon's IFX90ATX300W solution exceeds by at least 0.35 percentage points (at 50 percent load), making it reproducible in high-volume quantities.