On Semi 公司的NCP1654是电源功率因素控制器,与IEC61000−3−2兼容,平均电流连续导通模式(CCM),具有快速瞬态响应特性和非常少的外接元件,起动电流低于75uA,关断电流小于400uA,主要应用于平板电视,台式计算机,AC适配器,白色家电和其它离线开关电源(SMPS).本文介绍了NCP1654的主要特性,功能方框图, 软起动方框图, 300W 65kHz功率因素修正电路以及NCP1654EVB评估板主要特性,电路图和所用材料清单.

NCP1654 Power Factor Controller for Compact and Robust, Continuous Conduction Mode Pre-Converters

The NCP1654 is a controller for Continuous Conduction Mode (CCM) Power Factor Correction step−up pre−converters. It controls the power switch conduction time (PWM) in a fixed frequency mode and in dependence on the instantaneous coil current.

Housed in a SO8 package, the circuit minimizes the number of external components and drastically simplifies the PFC implementation. It also integrates high safety protection features that make the NCP1654 a driver for robust and compact PFC stages like an effective input power runaway clamping circuitry.

NCP1654主要特性:

IEC61000−3−2 Compliant

Average Current Continuous Conduction Mode

Fast Transient Response

Very Few External Components

Very Low Startup Currents (<75 uA)

Very Low Shutdown Currents (< 400uA)

Low Operating Consumption

1.5 A Totem Pole Gate Drive

Accurate Fully Integrated 65/133/200 kHz Oscillator

Latching PWM for cycle−by−cycle Duty−Cycle Control

Internally Trimmed Internal Reference

Undervoltage Lockout with Hysteresis

Soft−Start for Smoothly Startup Operation

Shutdown Function

Pin to Pin Compatible with Industry Standard

This is a Pb−Free Device

NCP1654安全特性:

Inrush Currents Detection

Overvoltage Protection

Undervoltage Detection for Open Loop Detection or Shutdown

Brown−Out Detection

Soft−Start

Accurate Overcurrent Limitation

Overpower Limitation

NCP1654典型应用:

Flat TVs, PC Desktops

AC Adapters

White Goods, other Off−line SMPS

图1.NCP1654功能方框图

图2.NCP1654 OVP和快速瞬态响应特性

图3.NCP1654软起动方框图

图4.NCP1654应用电路:300W 65kHz功率因素修正电路

NCP1654EVB评估板

The NCP1654EVB is a Power Factor Controller to efficiently drive Continuous Conduction Mode (CCM) step-up pre-converters. The NCP1654 allows operation in Follower Boost mode to drastically lower the pre-converter size and cost, in a straight-forward manner. The NCP1654 is a continuous conduction mode and fixed frequency controller (65kHz). The coil (650 uH) is selected to limit the peak to peak current ripple in the range of 36 % at the sinusoid top, in full load and low line conditions.

NCP1654EVB评估板主要特性:

Fast Transient Response

Low Operating Consumption

Inrush Currents Detection

Overvoltage Protection

Brown-Out Detection



图5.NCP1654EVB评估板外形图

图6.NCP1654EVB评估板电路图

NCP1654EVB评估板材料清单: