the tables and figures refer to the International Efficiency Marking Protocol for EPS. Compliant EPSs use the corresponding Roman numeral marking on their package. IPS efficiency programs are not very common due to the difficulty in identifying where the power supply's output can be tested if incorporated on the end application's circuit board. But because a computer's IPS is typically a discrete silver box with easily identifiable outputs, the 80 PLUS program was established for that product. Universally adopted, the voluntary 80 PLUS computer power supply labeling program specifies minimum efficiencies at 20, 50, and 100% loading [7]. It created performance group designations as shown in Table 3. ENERGY STAR was the first to incorporate the 80 PLUS standard level into its 2007 version 4 computer program specification, a level maintained through its current version 6 [8]. Table 3. The 80 PLUS minimum IPS efficiency requirements. 115-V Internal Power supplies 80 PLUS Designation 10% Load Efficiency 20% Load Efficiency 50% Load Efficiency 100% Load Efficiency Power Factor Correction Standard - 80% 80% 80% 0.9 at 100% load Bronze - 82% 85% 82% 0.9 at 50% load Silver - 85% 88% 85% 0.9 at 50% load Gold - 87% 90% 87% 0.9 at 50% load Platinum - 90% 92% 89% 0.95 at 50% load Titanium 90% 92% 94% 90% 0.95 at 20% load 230-V EU Internal Power supplies 80 PLUS Designation 10% Load Efficiency 20% Load Efficiency 50% Load Efficiency 100% Load Efficiency Power Factor Correction Standard - 82% 85% 82% 0.9 at 50% load Bronze - 85% 88% 85% 0.9 at 50% load Silver - 87% 90% 87% 0.9 at 50% load Gold - 90% 92% 89% 0.9 at 50% load Platinum - 92% 94% 90% 0.95 at 50% load Titanium 90% 94% 96% 94% 0.95 at 20% load 95 90 85 80 75 70 65 60 55 50 Minimum Average Efficiency (Standard Voltage) > 1 W 89% 88% 87% 85% 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 Nominal Power (Watts) CoC v5 (Tier 2) Ecodesign Dir. (Lev. V) U.S. DOE 2016 (Lev. VI) Previous U.S. DOE (Lev. IV) FIG 2 The ac-dc single-output EPS standard voltage four-point efficiency requirements. 22 IEEE PowEr ElEctronIcs MagazInE z March 2017 Four-Point Average Efficiency (%) Four-Point Average Efficiency (%) EU: European Union. Source: www.plugloadsolutions.com/80PlusPowerSupplies.aspx. 90 Minimum Average Efficiency ((Low Voltage) g )>1W 85 80 88% 87% 86% 85% 75 70 65 60 55 50 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 EPS Output Power (W) CoC v5 (Tier 2) Ecodesign Dir. (Lev. V) U.S. DOE 2016 (Lev. VI) Previous U.S. DOE (Lev. IV) FIG 3 The ac-dc single-output EPS low-voltage four-point efficiency requirements.http://www.plugloadsolutions.com/80PlusPowerSupplies.aspx