Fairchild公司的FSEZ1317NY是第三代初级边调整(PSR)和高度集成PWM控制器,待机功耗低于300mW,高压起动,具有最少的外接元件,没有次级反馈电路的恒压(CV)和恒流(CC)控制,PWM固定频率50kHz,主要用在手机,无绳电话,PDA,数码相机等充电器,替代线性变压器和RCC开关电源(SMPS)。本文介绍了FSEZ1317主要特性, 功能方框图, 简化PSR反激转换器电路图, 高压起动电路图和6W LED照明驱动器主要特性,电路图和变压器电路图。
FSEZ1317: Primary-Side-Regulation PWM with POWER MOSFET Integrated
This third-generation Primary-Side-Regulation (PSR) and highly integrated PWM controller provides several features to enhance the performance of low-power flyback converters. The proprietary topology, TRUECURRENT(TM), of FSEZ1317 enables precise CC regulation and simplified circuit design for batterycharger applications. A low-cost, smaller, and lighter charger results, as compared to a conventional design or a linear transformer.
To minimize standby power consumption, the proprietary green mode 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 the FSEZ1317, a charger can be implemented with few external components and minimized cost.
FSEZ1317主要特性:
Low Standby Power Under 30mW
High-Voltage Startup
Fewest External Component Counts
Constant-Voltage (CV) and Constant-Current (CC) Control without Secondary-Feedback Circuitry
Green-Mode: Linearly Decreasing PWM Frequency
Fixed PWM Frequency at 50kHz with Frequency Hopping to Solve EMI Problem
Cable Compensation in CV Mode
Peak-Current-Mode Control in CV Mode
Cycle-by-Cycle Current Limiting
VDD Over-Voltage Protection with Auto Restart
VDD Under-Voltage Lockout (UVLO)
Gate Output Maximum Voltage Clamped at 15V
Fixed Over-Temperature Protection with Auto Restart
Available in the 7-Lead SOP and DIP Packages
FSEZ1317应用:
Battery chargers for cELlular phones, cordless phones, PDA, digital cameras, power tools, etc.
Replaces linear transformers and RCC SMPS
图1. FSEZ1317功能方框图
图2. FSEZ1317简化PSR反激转换器电路图
图3. FSEZ1317高压起动电路图
图4. FSEZ1317典型应用电路图
6W LED照明驱动器
The following reference design supports inclusion of FSEZ1317NY in design of LED illumination.
6W LED照明驱动器主要特性:
Constant-Voltage (CV) and Constant-Current (CC) Control without Secondary- Feedback Circuitry
Built in 700V/1A MOSFET
Low EMI through Frequency Hopping
Low Power Consumption in Standby
Protection Functions: UVLO, Over-Voltage, Over-Current, and Over-Temperature
图6. 6W LED照明驱动器变压器电路图