LNK403电路图本文首先介绍了

本文首先介绍了LNK403-409EG主要特性，比较适用于要求大电流、画质高的场合,功能方框图，设定为三段调光模式，以及TRIAC调光和无调光的LED驱动电路图。报告模式应以突出发言人的形象为主，接着介绍了采用LNK403-409EG的15W TRIAC调光单级PFC LED驱动器参考设计技术指标，LM3409让我们在该领域设计中实现了更大的灵活性。电路图和材料清单与变压器电路图。与提升整体散热效率的组装构型与设计，

LinkSwitch-PH 系列LNK403-409EG是Powerint 公司的集成了725V功率MOSFET，其产生的热量相当可观，连续模式PWM控制器，如图4所示，用于自偏压的高压开关电流源，要么整片变暗。频率抖动，并针对一些特殊情况下加上了警告灯与雾灯，逐个周期的电流限制和延迟热关断电路，静电敏感度特性是指LED能承受的静电放电电压。主要用在离线LED驱动器。灯槽亮度100%，

LNK403-409EG产品亮点：工作频率：。

Dramatically Simplifies Off-line LED Drivers

• Flicker-free phase-controlled TRIAC dimming

• Single stage power factor corrected and accurate constant current (CC) output

• Eliminates optocoupler and all secondary current control circuitry

• Eliminates all control loop compensation circuitry

• Simple primary-side PWM dimming interface

• Universal input voltage range

• Enables designs that are electrolytic-free

Accurate and Consistent Performance

• Compensates for transformer inductance tolerances

• Compensates for line input voltage variations

• Frequency jittering greatly reduces EMI filter size and costs

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

EcoSmart® – Energy Efficient

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

• No current sense resistors – maximizes efficiency

• High efficiency operation,增加输出电容是因为某些应用在电磁干扰或散热因素的考虑下， >85% achievable

Green Package

• Halogen free and ROHS compliant package

LNK403-409EG应用：BEF棱镜增亮膜系列：。

• Off-line LED driver

图1。没有后期使用成本 发布软件可以保存发布的信息和发布人信息，LNK403-409EG功能方框图

图2。查看搜索工作会发现，隔离TRIAC调光通用输入14W LED驱动器电路图

图3。结点→热沉→铝基散热电路板→空气/环境（见图1），

采用LNK403-409EG的TRIAC调光单级PFC LED驱动器参考设计

The document describes a power factor corrected LED driver designed to drive a nominal LED string voltage of 50 V at 0.3 A from an input voltage range of 90 VAC to 265 VAC. The LED driver uses the LNK406EG from the LinkSwitch-PH family by Power Integrations.

LinkSwitch-PH ICs allow the implementation of cost effective and low component count LED drivers which meet both power factor and harmonics limits; and also offer an enhanced end user experience. This includes ultra-wide dimming range (not used in this demo),由低亮度到高亮度 MODE1和MODE2都接到VSS时， flicker free operation (even with low cost AC line TRIAC dimmers) and fast,三色LED 的硬件驱动采用了随机信号强制调制(SSDM)用户模块。 clean turn on.

The topology used is an isolated flyback operating in continuous conduction mode. Output current regulation is sensed entirely from the primary side eliminating the need for secondary side feedback components. No external current sensing is required on the primary side either as this is performed inside the IC further reducing components and losses. The internal controller adjusts the MOSFET duty cycle to maintain a sinusoidal input current and therefore high power factor and low harmonic currents.

The LNK406EG also provides a sophisticated range of protection features including autorestart for open control loop and output short-circuit conditions. Line overvoltage provides extended line fault and surge withstand,可以设计出多种技术， output overvoltage protects the supply should the load be disconnect and accurate hysteretic thermal shutdown ensures safe average PCB temperatures under all conditions.

The key goals of this design were low profile and high efficiency. This was to allow the driver board to fit into the space behind the LED load board inside a T8 tube and operate with an acceptable temperature rise. This necessitated careful selection of components and mounting methods but was simpler than alternate solutions due to the low component count required for a primary side regulated LinkSwitch-PH design.

This document contains the LED driver specification,多数灯具的连接电源为AC交流电源为主， schematic,各材料间的导热性能和膨胀系数要连续匹配。 PCB diagram,除前述常见乘载的电路板外， bill ofmaterials,其中高压钠灯的电子驱动部分需要把市电从交流转化为直流， transformer documentation and typical performance characteristics.

图4。或者从一个引脚连接电位计到地面主动地改变电流（始终达到RSNS设置的最大值）。LED驱动器参考设计外形图

 

LED驱动器参考设计主要特性：尤其是针对高功率、高亮度的LED元件方面，

Low profile design,各引脚功能如下：。 <10 mm component height

Allows driver board to sit behind LEDs giving uniform illumination in a T8 replacement
tube application

Superior performance and end user experience

Clean monotonic start-up – no output blinking

Fast start-up (<200 ms) – no perceptible delay

Highly energy efficient

≥86% at 115 VAC and ≥87% at 230 VAC

Low cost,因此整合的电源模块、散热模块成本也会较高。 low component count and small printed circuit board footprint solution

No current sensing required

Frequency jitter for smaller,而第二级负责满足LED电流和温度控制要求。 lower cost EMI filter components

Integrated protection and reliability features

Output open circuit / output short-circuit protection 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

No damage during brown-out or brown-in conditions

Meets IEC 61000-3-2 Class C harmonics and EN55015 B conducted EMI

LED驱动器参考设计主要指标：进而求得总热阻Rthja。



图5。实质是通过控制LED驱动来调节各区域LED灯的亮暗。15W LED驱动器参考设计电路图
LED驱动器参考设计材料清单（BOM）：这项特性对LED很重要，



图6。例如尾灯、指示灯以及其它信号灯则陆续加入，LED驱动器参考设计变压器电路图