【摘要】 分析设计了一款新颖的功率因数校正(PFC)电路,该电路可以工作于不连续传导模式(DCM)和临界连续传导模式(CRM),并实现两种模式的自动切换,兼具两种工作模式的优势。在输入电压跨零附近,电路工作于固定频率的DCM下,限制最大的开关频率,从而降低污染系统的电磁干扰(EMI)噪声。在输入电压峰值附近,电路工作于频率可变的CRM下,降低升压二极管、功率MOSFET和电感上的电流应力,从而降低费用并且提高电路的可靠性。采用台联电0.6μmBCD工艺仿真验证,得到了近1的功率因数。更多还原

【Abstract】 The PFC circuit described in this paper could operate in Discontinuous Conduction Mode (DCM) and Critical Conduction Mode (CRM) and takes advantages from both operating modes. When the input voltage is around zero, the circuit works in fixed frequency DCM. It limits the maximum switching frequency and reduces the EMI noise that may pollute surrounding systems. When the input voltage is around the sinusoidal peak, the circuit works in variable frequency CRM. It reduces the maximum current stress of the boost stage diode, power MOSFET and inductor and reduces the costs and improves the reliability of the circuit. This device substantially exhibits unity power factor while operating in DCM and CRM.更多还原