Fairchild公司的FAN104W是高频初级调整的PWM控制器,能提高低功率反激转换器的性能.待机功耗小于30mW,满足能量之星五星标准,突发模式工作电流600uA,具有输出短路保护,输出过压保护(VSOVP),VDD过压保护和超温保护等功能,主要用在智能手机,PAD,PDA和数码相机电池充电器等.本文介绍了FAN104W主要特性,方框图,典型应用电路以及10W平板电脑和智能手机充电器参考设计主要特性,电路图,变压器电路和PCB布局图.

This highly integrated PWM controller, FAN104W, provides several features to enhance the performance of low-power flyback converters. The proprietary topology of FAN104W enables simplified circuit design for battery charger applications. The result is a lowercost,smaller, and lighter charger compared to a conventional design or a linear transformer.To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to linearly decrease PWM frequency under light-load conditions. Green Mode assists the power supply in meeting power conservation requirements. By using FAN104W, a charger can be implemented with few external components and minimized cost.

FAN104W主要特性:

 Achieves <30 mW; Energy Star’s 5-Star Level

 Proprietary 500 V High-Voltage JFET Startup Reduces Startup Resistor Loss

 Low Operation Current in Burst Mode: 600 μA

 Constant-Voltage (CV) and Constant-Current (CC)

Control without Secondary-Feedback Circuitry

 Green Mode: PWM Frequency Linearly-Decreasing

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

 Boundary-Conduction-Mode (BCM) Operation at Lower AC Input Voltage

 Cable Compensation in CV Mode

 Cycle-by-Cycle Current Limiting

 Gate Output Maximum Voltage Clamped at 14 V

 VDD Under-Voltage Lockout (UVLO) Available

 Built-in Protections:

- Output Short-Circuit Protection

- Output Over-Voltage-Protection (VSOVP) with Latch Mode

- VDD Over-Voltage-Protection (VDD OVP)

- CS Pin Single-Fault Protection

- VS Pin single-Fault Protection

- Over-Temperature-Protection (OTP) with Latch Mode

 SOIC Package

FAN104W应用:

 Battery chargers for smart phones, Pad, PDA,digital cameras.

 Best choice to replace linear transformer and RCC SMPS

图1.FAN104W方框图

图2.FAN104W典型应用电路图

10W平板电脑和智能手机充电器参考设计


This reference design supports inclusion of the FAN104W in the design of a 10W charger with BCM operation and Primary-Side Regulation (PSR) technology. It should be used in conjunction with the FAN104W datasheet as well as Fairchild’s application notes and technical support team.

10W充电器参考设计主要特性:

Low Standby-Power Consumption: < 50mW at 264VAC

Constant-Voltage (CV) and Constant-Current (CC) Control without Secondary-Feedback Circuitry

PWM Frequency at 85kHz with Frequency Hopping to Reduce EMI

Frequency-Reduction Technology for BCM Operation

Cable-Voltage-Drop Compensation in CV Mode

High-Voltage Startup

Low Burst-Mode Operating Current: 600A(Typical) and Normally-Operating Current: 3.5mA (Typical)

Output Over-Voltage Protection (OVP), VDD Over-Voltage Protection (OVP),VDD Under-Voltage Lockout (UVLO), Over-Temperature Protection (OTP),CS-Pin- Short Protection, VS-Pin Single-Fault Protection

SOIC-8 Package

图3.10W充电器参考设计电路图

图4.10W充电器参考设计变压器电路图

图5.10W充电器参考设计外形图

图6.10W充电器参考设计PCB布局图

详情请见:
http://www.fairchildsemi.com/ds/FA/FAN104W.pdf
和
http://www.fairchildsemi.com/support/referencedesign/docs/RD-FAN104WMD-T06U010A.pdf