On Semi NCP1611 160W PFC电源解决方案
On Semi公司的NCP1611是采用创新的电流控制频率折返(CCFF)方法的驱动PFC升压级,功率因素接近1, 高驱动能力为 −500 mA / +800 mA, VCC范围从9.5V到35V,具有非闭锁和过压保护,电压检测,软起动和过流限制,主要用在PC电源,需要PFC的所有离线电器电源.本文介绍了NCP1611主要特性,方框图,通用应用电路以及160W PFC电源评估板指标,电路图和材料清单.
The NCP1611 is designed to drive PFC boost stages based on an innovative Current Controlled Frequency Fold−back (CCFF) method. In this mode, the circuit classically operates in Critical conduction Mode (CrM) when the inductor current exceeds a programmable value. When the current is below this preset level, the NCP1611 linearly decays the frequency down to about 20 kHz when the current is null. CCFF maximizes the efficiency at both nominal and light load. In particular, the standby losses are reduced to a minimum.
Like in FCCrM controllers, internal circuitry allows near−unity power factor even when the switching frequency is reduced. Housed in a SO−8 package, the circuit also incorporates the features necessary for robust and compact PFC stages, with few external components.
NCP1611主要特性:
Near−Unity Power Factor
Critical Conduction Mode (CrM)
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