Fairchild公司的FL7730MY是单级初级边调整的PWM控制器,为单级反激转换器提供了增强性能,采用的TRUECURRENT™拓扑能简化LED照明应用的电路设计,从而降低成本,提高了功率因素,降低总谐波失真.起动电流20uA,工作电流5mA,主要于LED照明.本文介绍了FL7730MY主要特性,方框图, 输入电压90-140VAC的TRIAC调光LED驱动电路图以及90V-264VAC的评估板5.0V/0.7A手机电池充电器主要指标,电路图,材料清单和PCB布局图.
FL7730MY:Single-Stage Primary-Side-Regulation PWM Controller for PFC and LED Dimmable Driving
This highly integrated PWM controller, FL7730MY, provides several features to enhance the performance of single-stage flyback converters. The proprietary topology, TRUECURRENT™, enables the simplified circuit design for LED lighting applications.
TRIAC dimming is smoothly managed by dimming brightness control without flicker. By using single-stage topology with primary-side regulation, an LED lighting board can be implemented with few external components and minimized cost. It does not require an input bulk capacitor or feedback circuitry. To implement good power factor and low total harmonic distortion, constant on-time control is utilized with an external capacitor connected to the COMI pin.
Precise constant-current control regulates accurate output current versus changes in input voltage and output voltage. The operating frequency is proportionally changed by the output voltage to guarantee Discontinuous Conduction Mode (DCM) operation with higher efficiency and simpler design. The FL7730MY provides protections such as open-LED, short-LED, and over-temperature protections. Current-limit level is automatically reduced to minimize output current and protect external components in a short-LED condition.
The FL7730MY frequency-hopping function in the oscillator improves EMI performance. The FL7730MY controller is available in an 8-pin SOP package.

FL7730MY主要特性:
 Compatible with Traditional TRIAC Control (No need to change existing lamp infrastructure: wall switch & wire)
 Compatible with Non-Dimming Lamp Designs
 Cost-Effective Solution without Input Bulk Capacitor and Feedback Circuitry
 Power Factor Correction (PFC)
 Accurate Constant-Current (CC) Control, Independent Online Voltage, Output Voltage,Magnetizing Inductance Variation
 Line Voltage Compensation for CC Control
 Linear Frequency Control for Better Efficiency and Simple Design
 Open-LED Protection
 Short-LED Protection
 Cycle-by-Cycle Current Limiting
 Over-Temperature Protection with Auto Restart
 Low Startup Current: 20μA
 Low Operating Current: 5mA
 Frequency Hopping for Better EMI Performance
 SOP-8 Package Available

FL7730MY应用:
 LED Lighting System

图1.FL7730MY方框图

图2.FL7730MY TRIAC调光LED驱动电路图(输入电压90-140VAC)

FEBFSEZ1317A_CH310v3评估板5.0V/0.7A手机电池充电器
This document describes a 3.5W power supply using an FSEZ1317AMY device. This power supply is targeted for mobile phone battery chargers for a 30mW solution with high efficiency.
The controller used on the board is Fairchild Semiconductor’s FSEZ1317AMY. This third-generation Primary-Side-Regulation (PSR) PWM controller with integrated MOSFET and improved EMI performance provides several features to enhance the performance of low-power flyback converters. The proprietary TRUECURRENT® technology enables precise Constant Current (CC) regulation and simplified circuit design for battery-charger applications. The result is a lower-cost, smaller, and lighter charger compared to conventional designs or a linear transformer. To minimize standby power consumption (30mW at 265VAC), a 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 FSEZ1317A, a charger can be implemented with few external components and minimized cost.

5.0V/0.7A手机电池充电器主要指标:


图4.5.0V/0.7A手机电池充电器外形图

图5.5.0V/0.7A手机电池充电器电路图

5.0V/0.7A手机电池充电器材料清单:




图6.5.0V/0.7A手机电池充电器PCB布局图:上:顶层,中:中间层,下:底层