Factor PFC Into Your Power-Supply Design (PDF Download)

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Before the latest IEC61000-3-2 standard took effect in 2005, most power supplies for PCs, monitors, and TVs generated excessive line harmonics when operating from single-phase, 110- to 120-V, 60-Hz ac. Spurred on by this newer and stricter IEC standard, power-supply manufacturers aim to minimize power-line harmonics by adding power factor correction (PFC).

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