NCP1681 Series

Totem-Pole Continuous Conduction Mode (CCM) / Multi-mode (CrM-CCM) Power Factor Correction Controller

Catalog

Totem-Pole Continuous Conduction Mode (CCM) / Multi-mode (CrM-CCM) Power Factor Correction Controller

Part	Frequency - Switching	Mode	Mounting Type	Voltage - Supply	Supplier Device Package	Package / Case [y]	Package / Case	Package / Case [x]	Package / Case
ON Semiconductor NCP1681AAD2R2G	65 kHz	Continuous Conduction (CCM)	Surface Mount	30 VDC	20-SOIC	3.9 mm	18 Leads	0.154 in	20-LSOP

Catalog

Totem-Pole Continuous Conduction Mode (CCM) / Multi-mode (CrM-CCM) Power Factor Correction Controller

Key Features

• Totem Pole PFC Topology Eliminates Input Diode Bridge

• Continuous Conduction Mode (CCM) Operation At High Power Level

• Optional Multi-mode Operation With CCM at High Power & CrM at Medium Power Level

• Frequency Foldback in DCM With 25 kHz Minimum Frequency

• Skip Mode in Very Light Load Condition

• Novel Current Sense Scheme

• Digital Voltage Loop Compensation

• AC Line Monitoring Circuit & AC Phase Detection

• Near Unity Power Factor in All Operating Modes

• PFC OK Indicator

Description

The NCP1681 is a PFC controller IC designed to drive the bridgeless totem-pole PFC topology. The bridgeless totem-pole PFC is a power factor correction architecture that consists of a fast switching leg driven at the PWM switching frequency and a second leg that operates at the AC line frequency. This topology eliminates the diode bridge present at the input of a conventional PFC circuit, allowing significant improvement in the power stage efficiency. The controller can be configured to operate in Continuous Conduction Mode (CCM) or Multi-Mode (CrM-CCM) operation.