OnSemi NPC1612 160W宽电压输入PFC驱动方案

OnSemi公司的NCP1612是一款采用创新的CCFF（Curret Controlled Frequency Fold-back）方式的PFC增压阶段芯片，在这种模式下，当电感电流超过预设值时，典型工作电路工作在临界导通模式。当电流低于该预设值时，NCP1612线性降低频率下降到约20千赫时，电流值最终降至零。特别是待机的损失减少到最低限度。控制器提供了一整套功能强大的保护功能，能够妥善处理好电源阵列的运行和故障情况。本文主要介绍了该芯片的主要特性及功能强大的保护特性，并给出芯片内部框图、方案介绍、方案原理图、方案PCB图及元器件列表。

The NCP1612 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 NCP1612 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 stand−by losses are reduced to a minimum.

Like in FCCrM controllers, an internal circuitry allows near−unity power factor even when the switching frequency is reduced. Housed in a SO−10 package, the circuit also incorporates the features necessary for robust and compact PFC stages, with few external components.

NCP1612主要特性：

• Near−Unity Power Factor
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