原标题：Fairchild FAN302HL低待机功耗PWM电源控制方案

　　Fairchild公司的FAN302HL是低待机功耗电池充电器用的PWM电源控制器, 采用恒流模式控制,在230VAC时的带机功耗低于10mW,固定PWM频率85kHz和跳频,以降低EMI,工作电流3.5A,栅极输出最大电压箝位在 15V,具有高压起动功能,主要用在手机,无绳电话,PDA和数码相机等电池充电器.本文介绍了FAN302HL主要特性, 功能方框图, 高压(HV)起动电路图, 反激转换器电路图和典型应用电路图以及变压器结构图和绕组指标.

　　FAN302HL PWM Controller for Low Standby Power Battery-Charger Applications

　　This highly integrated PWM controller, FAN302HL, provides several features to enhance the performance of general flyback converters. The constant-current control, proprietary topology enables simplified circuit designs without secondary feedback circuitry for batterycharger applications.

　　A proprietary Burst-Mode function with low operation current minimizes standby power consumption.

　　The FAN302HL controller also provides several protections. Cycle-by-cycle current limiting ensures the fixed peak current limit level, even if a short circuit occurs. The gate output is clamped at 15V to protect the power MOS from high gate-source voltage conditions. If either VS OVP or internal OTP is triggered, the circuit enters Latch Mode until AC power is removed.

　　Using FAN302HL, a charger can be implemented with few external components and minimized cost, compared to a conventional design or a linear transformer.

　　FAN302HL主要特性:

　　Ultra-Low Standby Power: Under 10mW at 230VAC

　　Constant-Current (CC) Control without Secondary- Feedback Circuitry

　　Fixed PWM Frequency at 85kHz with Frequency Hopping to Solve EMI Problem

　　High-Voltage Startup

　　Low Operating Current: 3.5mA

　　Peak-Current-Mode Control in CV Regulation

　　Cycle-by-Cycle Current Limiting

　　VDD Over-Voltage Protection (Auto-Restart)

　　VS Over-Voltage Protection (Latch Mode)

　　VDD Under-Voltage Lockout (UVLO)

　　Gate Output Maximum Voltage Clamped at 15V

　　Fixed Over-Temperature Protection (Latch Mode)

　　Available in an 8-Lead SOIC Package

　　FAN302HL应用:

　　Battery chargers for cellular phones, cordless phones, PDA, digital cameras, and power tools. Replaces linear transformers and RCC SMPS.

　　图1.FAN302HL功能方框图

　　图2.FAN302HL简化反激转换器电路图

　　图3.FAN302HL高压(HV)起动电路图

　　图4.FAN302HL典型应用电路

　　图5.FAN302HL典型应用电路图

　　图6.FAN302HL变压器结构图

　　变压器绕组指标: