Description
The FAN6961 is an 8-pin, boundary-mode, PFC controller IC intended for controlling PFC pre regulators. The FAN6961 provides a controlled on-time to regulate the output DC voltage and achieve natural power factor correction. The maximum on-time of the external switch is programmable to ensure safe operation during AC brownouts. An innovative multivector error amplifier is built in to provide rapid transient response and precise output voltage clamping. A built-in circuit disables the controller if the output feedback loop is opened. The start-up current is lower than 20µA and the operating current has been reduced to under 6mA. The supply voltage can be up to 25V, maximizing application flexibility.

Features
■ Boundary Mode PFC Controller
■ Low Input Current THD
■ Controlled On-Time PWM
■ Zero-Current Detection
■ Cycle-by-Cycle Current Limiting
■ Leading-Edge Blanking instead of RC Filtering
■ Low Start-up Current: 10µA Typical
■ Low Operating Current: 4.5mA Typical
■ Feedback Open-Loop Protection
■ Programmable Maximum On-Time (MOT)
■ Output Over-Voltage Clamping Protection
■ Clamped Gate Output Voltage 16.5V

Applications
■ Electric Lamp Ballasts
■ AC-DC Switching Mode Power Converter
■ Open Frame Power Supplies and Power Adapters
■ Flyback Power Converters with ZCS / ZVS