PFC Controller Boosts Efficiency While Raising Reliability

The UCC28070 two-phase, average current-mode power-factor correction (PFC) controller allows designers to simplify power design, increase system reliability, and achieve a greater than 0.9 power factor rating to boost efficiency. The device is the first single-chip, interleaved PFC control circuit for multi-kilowatt communications, server, and industrial systems. In line-operated systems with power levels from 75W to 1 kW and above, the UCC28070 helps reduce total harmonic distortion, allowing today’s systems to maximize usable outlet power and accommodate extreme variations and disturbances in various ac line voltage levels used around the world. The controller allows light-load phase management, which lets a system turn on or off phases of the power supply, so that only the phases required to power the load are enabled. In a 1.2-kW system, the UCC28070 can increase efficiency by up to 1.5% at a light 20% load condition, allowing designers to exceed energy guidelines set forth by industry initiatives such as The Green Grid, Climate Savers Computing Initiative, and Project Big Green. In a 240W supply at a 20% load condition, this increase in efficiency results in a 27% power savings. The UCC28070 comes in a 20-pin TSSOP. It is sampling today, with volume production scheduled for January 2008. Price is $2.45 each/100. TEXAS INSTRUMENTS INC., Dallas, TX. (800) 477-8924.