</a>LED" title="LED">LED" title="LED">LED驱动器系列,单级PFC,初级恒流控制,可选择TRIAC调光/不调光,不需要光耦和电流检测电路.器件集成了725V功率FET,连续模式PWM控制器,用于自偏压的高压开关电流源,频率抖动和保护电路,从大局出发大大简化了离线LED驱动器,主要用于离线LED驱动器.本文介绍了LinkSwitch-PH系列产品亮点,方框图,14W和7W LED驱动电路图,以及采用LNK419EG的40.5W街灯LED照明电路参考设计主要特性和指标,电路图,材料清单和PCB元件布局图.

 The LinkSwitch-PH dramatically simplifies implementation of LED drivers requiring long lifetime, high efficiency, PF >0.9, and TRIAC dimming capability (LNK403-410). The single-stage combined power factor and constant-current controller eliminates a switching stage and the electrolytic bulk capacitor. The advanced primary-side control used by the LinkSwitch-PH device provides accurate constant current control while eliminating the need for an optocoupler and current sensing circuits.

LinkSwitch-PH incorporates a 725 V power FET, a continuous-mode PWM controller, a high-voltage switched current source for self biasing, frequency jittering, protection circuitry including cycle-by-cycle current limit and hysteretic thermal shutdown.

LinkSwitch-PH系列产品亮点:

Dramatically Simplifies Off-line LED Drivers

• Single-stage combination of power factor correction and accurate constant-current (CC) output

• Enables very long lifetime designs (no electrolytic capacitors)

• Eliminates optocoupler and all secondary current control circuitry

• Eliminates control loop compensation circuitry

• Simple primary-side PWM dimming interface

• Universal input voltage range

• LNK403-410 optimized for flicker-free TRIAC dimming EcoSmart™ – Energy Efficient

• Single-stage PFC combined with output CC control

• Greatly increases efficiency, >90% achievable

• Reduces component count

• No current sense resistors

• Low standby power remote ON/OFF feature (<50 mW at 230 VAC)

Accurate and Consistent Performance

• Compensates for transformer inductance variations

• Compensates for line input voltage variation

• Frequency jittering greatly reduces EMI filter size and cost

Advanced Protection and Safety Features

• Auto-restart for short-circuit protection

• Open circuit fault detection mode

• Automatic thermal shutdown restart with hysteresis

• Meets high voltage creepage requirement between DRAIN and all other signal pins both on PCB and at package

Green Package

• Halogen free and ROHS compliant package

LinkSwitch-PH系列应用:

• Off-line LED driver

图1.LinkSwitch-PH系列方框图

图2.LinkSwitch-PH系列通用输入TRIAC调光14W LED驱动电路图
 

图3.LinkSwitch-PH系列通用输入无调光7W LED驱动电路图

采用LinkSwitchTM-PH LNK419EG的40.5W功率因素大于0.95的非隔离降压LED驱动器参考设计

The document describes a non-isolated high power factor (PF) LED driver designed to drive a nominal LED string voltage of 54 V at 750 mA from an input voltage range of 90 VAC to 300 VAC. The LED driver utilizes the LNK419EG from the LinkSwitch-PH family of ICs.

The topology is a single-stage non-isolated buck converter that meets the high efficiency requirements for this design. Good line and load output current regulation is achieved by directly sensing the output current and using shunt regulator for closed-loop feedback control.

High power factor and low THD is achieved by employing the LinkSwitch-PH IC which also provides a sophisticated range of protection features including auto-restart to prevent damage in the event of open control loop or during output short-circuit. Line overvoltage protection provides extended line fault and surge withstand. Output overvoltage protects the supply should the load be disconnected. Accurate hysteretic thermal shutdown ensures safe PCB temperatures under all conditions.

This document contains the LED driver specification, schematic, PCB diagram, bill of materials, transformer documentation and typical performance characteristics.

40.5W LED驱动器主要特性:

 Highly energy efficient

 >88% at 230 VAC

 >87% at 120 VAC

 <2% line and load regulation

 <5% IOUT tolerance

 Low cost, low component count and small, single-sided printed circuit board

 Frequency jitter allows smaller, lower cost EMI filter

 Integrated protection and reliability features

 Output open circuit / output short-circuit protected with auto-recovery

 Line input overvoltage shutdown extends voltage withstand during line faults

 Auto-recovering thermal shutdown with large hysteresis protects both components and printed circuit board

 IEC 61000-4-5, IEC 61000-3-2 Class C, and EN55015 B conducted EMI compliant


图4.40.5W LED驱动器外形图
40.5W LED驱动器主要性能指标:


图5.40.5W LED驱动器电路图

40.5W LED驱动器材料清单(BM):



图6.40.5W LED驱动器 PCB元件布局图(顶层)

图7.40.5W LED驱动器 PCB元件布局图(底层)
详情请见:
http://www.powerint.com/sites/default/files/product-docs/linkswitch-ph_family_datasheet.pdf
和
http://www.powerint.com/sites/default/files/PDFFiles/der340.pdf