The NCP1652 is a highly integrated controller for implementing power factor correction (PFC) and isolated step down ac-dc power conversion in a single stage, resulting in a lower cost and reduced part count solution. This controller is ideal for notebook adapters, battery chargers and other off-line applications with power requirements between 75 W and 150 W. The single stage is based on the flyback converter and it is designed to operate in continuous conduction (CCM) or discontinuous conduction (DCM) modes.
The NCP1652 increases the system efficiency by incorporating a secondary driver with adjustable nonoverlap delay for controlling a synchronous rectifier switch in the secondary side, an active clamp switch in the primary or both. In addition, the controller features a proprietary Soft-Skip™ to reduce acoustic noise at light loads. Other features found in the NCP1652 include a high voltage startup circuit, voltage feedforward, brown out detector, internal overload timer, latch input and a high accuracy multiplier.

• Dual Control Outputs with Adjustable Non Overlap Delay for Driving a Synchronous Rectifier Switch, an Active Clamp Switch or Both
• Voltage Feedforward
• Frequency Jittering
• Proprietary Soft-Skip™ at Light Loads
• High Accuracy Multiplier
• Brown Out Detector
• Internal 150 ms Fault Timer
• Independent Latch-Off Input Facilitates Implementation of Overvoltage and Overtemperature Fault Detectors
• Single Stage PFC and Isolated Step Down Converter
• Continuous or Discontinuous Conduction Mode Operation
• Average Current Mode Control (ACMC), Fixed Frequency Operation
• Adjustable Operating Frequency from 20 kHz to 250 kHz