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NCP1611
Enhanced, High-Efficiency Power Factor Controller
The NCP1611 is designed to drive PFC boost stages based on an
innovative Current Controlled Frequency Fold−back (CCFF)
method. In this mode, the circuit classically operates in Critical conduction Mode (CrM) when the inductor current exceeds a
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programmable value. When the current is below this preset level, the
NCP1611 linearly decays the frequency down to about 20 kHz when
MARKING
the current is null. CCFF maximizes the efficiency at both nominal
DIAGRAM
and light load. In particular, the stand−by losses are reduced to a minimum.
Like in FCCrM controllers, internal circuitry allows near−unity power factor even when the switching frequency is reduced.
NCP1611 Datasheet
