On Semi公司的NCP1615是高压高效功率因素修正(PFC)控制器,采用创新的电流控制频率折返(CCFF)方法,在正常和轻负载时最大化效率,特别是待机功耗降低到最低,而功率因素接近一.器件集成了高压起动电流不需要外接元件,并具有多种安全特性,主要用在PC电源,需要PFC的离线电器电源,LED驱动器和平板TV等.本文介绍了NCP1615主要特性和安全特性, 功能框图,典型应用电路以及评估板NCP1615GEVB电路图和材料清单.
The NCP1615 is a high voltage PFC controller designed to drive PFC boost stages based on an innovative Current Controlled Frequency Foldback (CCFF) method. In this mode, the circuit operates in critical conduction mode (CrM) when the inductor current exceeds a programmable value. When the current is below this preset level, the NCP1615 linearly decays the frequency down to a minimum of about 26 kHz at the sinusoidal zero−crossing. CCFF maximizes the efficiency at both nominal and light load. In particular, the standby losses are reduced to a minimum. Innovative circuitry allows near−unity power factor even when the switching frequency is reduced.
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