Powerint公司的LinkSwitch-PH系列大大地简化了实现功率因素大于0.9,TRIAC调光和高效率的LED驱动器的设计.器件集成了725V功率MOSFET,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,逐个周期限流和滞后热关断电路,最适合用于离线LED驱动器.本文介绍了LinkSwitch-PH系列产品亮点, 功能方框图, 14W和7W LED驱动器电路图,以及采用LNK417EG无电解电容高效率(≥90%) PFC大于0.9的15W LED驱动器参考设计电路图,主要指标和材料清单与PCB布局图.

LinkSwitch-PH dramatically simplifies implementation of LED drivers requiring Power Factors greater than 0.9, TRIAC dimming, and high efficiency. This highly integrated controller introduces a new control technique that provides very high power factor and accurate output current control, and eliminates passive circuitry required for power factor correction, optocoupler and secondary current control circuitry.

Each device incorporates a 725V power MOSFET, a continuous-mode PWM controller, a high voltage switched current source for self biasing, frequency jittering, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry into a monolithic IC.

LinkSwitch-PH系列产品亮点:

Dramatically Simplifies Off-line LED Drivers

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

Flicker-free, phase-controlled TRIAC dimming

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

Fast start-up time

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 or restart with hysteresis

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

EcoSmart - Energy-Efficiency Technology

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

No current sense resistors - maximizes efficiency

High efficiency operation, >85% achievable

Green Package

Halogen free and RoHS compliant package

LinkSwitch-PH应用:

• Off-line LED driver

图1. LinkSwitch-PH系列功能方框图

图2. LinkSwitch-PH系列绝缘TRIAC调光高功率因素通用输入14W LED驱动器电路图

图3. LinkSwitch-PH系列绝缘无调光高功率因素通用输入7W LED驱动器电路图 采用LNK417EG无电解电容高效率(≥90%) PFC大于0.9的15W LED驱动器参考设计

This document describes an isolated, power factor corrected, very high efficiency LED driver designed to drive a 30 V LED string at a current of 500 mA (nominal). The input voltage range is 90 VAC to 265 VAC.

The LED driver uses a LNK417EG device from the LinkSwitch-PH family of ICs. This integrated controller and 725 V MOSFET dramatically reduces the complexity and component count of the solution.

The key design goals were to achieve the highest possible efficiency and eliminate electrolytic capacitors. Both are key factors for increasing the lifetime and reliability of LED drivers making this solution ideal for industrial and commercial applications.

15W LED驱动器参考设计主要特性:

No electrolytic capacitors

Clean monotonic start-up – no output blinking

Fast start-up (<100 ms) – no perceptible delay

Highly energy efficient

o ≥90% at 115 VAC and 230 VAC input Low cost, low component count and small printed circuit board footprint solution

o No current sensing required

o Frequency jitter for smaller, lower cost EMI filter components Integrated protection and reliability features

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

o Line input overvoltage shutdown extends voltage withstand during line faults.

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

o No damage during brown-out or brown-in conditions

Meets IEC 61000-4-5 ring wave, IEC 61000-3-2 Class C harmonics and EN55015 B conducted EMI


图4.15W LED驱动器参考设计外形图: 3.115” L x 1.525” W.
电源指标:


图5.15W LED驱动器参考设计电路图


图6.变压器电路图
变压器主要指标:



图7. PCB布局图(顶层)