资 源 简 介
The UC1852 provides a low-cost soluTIon to acTIve power-factor correcTIon (PFC) for systems that would otherwise draw high peak current pulses from AC power lines. This circuit implements zero-current switched boost conversion, producing sinusoidal input currents with a minimum of external components, while keeping peak current substanTIally below that of fully-discontinuous converters.
The UC1852 provides controlled switch on-time to regulate the output bulk DC voltage, an off-time defined by the boost inductor, and a zero-current sensing circuit to reactivate the switch cycle. Even though switching frequency varies with both load and instantaneous line voltage, it can be maintained within a reasonable range to minimize noise generation.
