Powerint LNK409EG 25W T8管LED驱动解决方案

发布时间：2011-11-28 22:08 发布者：1046235000

Powerint公司的25W T8管灯LED驱动器采用LinkSwitchTM-PH LNK409EG器件,输入电压180 VAC到265 VAC,输出电压约100V,输出电流250A.该驱动器采用非隔离的降压-升压托扑,PFC和低THD(小于25%)和高效率(大于91%),和IEC61000-3-2 CLASS C兼容,不需要控制回路补偿和输出电流检测.本文介绍了T8管LED驱动器主要指标,电路图和材料清单.

T8 25 W, Non-Isolated, Buck-Boost Topology, Power Factor Corrected, LED Driver Using
LinkSwitchTM-PH LNK409EG

This document describes a non-isolated, power factor corrected, low THD, high-efficiency LED driver designed to drive ~100 V LED string at 250 mA from an input voltage range of 180 VAC to 265 VAC.

The LinkSwitch-PH has been developed to cost effectively implement a single-stage power factor corrected LED driver and primary-side constant-current control. The LinkSwitch-PH controller is optimized for LED driver applications and requires minimal external parts. It provides control of the output current through the LED load without the use of an optocoupler.

The LinkSwitch-PH monolithically integrates the 725 V power MOSFET and controller. The controller consists of an oscillator, PWM, 6 V regulator, over-temperature protection,frequency jittering, cycle-by-cycle current limit, leading edge blanking, and a charge controller for output CC (constant current) control.

The LinkSwitch-PH provides a sophisticated range of additional protection features including auto-restart for control loop open/short faults and output short-circuit conditions. The accurate hysteretic thermal shutdown ensures safe PCB temperatures under all conditions.

The non-isolated power factor corrected buck-boost design presented in this report shows how LinkSwitch-PH dramatically simplifies off-line, high-efficiency, power factor corrected LED driver design with very low parts count and enables a Class C harmonic currents compliant implementation of a very high efficiency, high output voltage design This document contains the LED driver specification, schematic, PCB diagram, bill of materials, conducted EMI measurements, thermal measurements, inductor documentation and typical performance characteristics.

T8管LED驱动器主要特性:

 Dramatically simplifies off-line, power factor corrected, LED driver design

 Single-stage, power factor corrected and constant current, non-isolated LED driver

 Compact with extremely low component count

 High PF >0.9 across line and load

 High efficiency >91% at 230 VAC

 Low THD, <25% at 230 VAC

 IEC61000-3-2 CLASS C compliant

 Eliminates all control loop compensation

 No output current sensing required

 Advanced performance features

 Compensates for inductance tolerance

 Compensates for input voltage variations

 Compensates for output voltage variations

 Frequency jittering greatly reduces EMI filter costs

 Advanced protection and safety features

 Auto-restart protection for short-circuit

 Hysteretic thermal shutdown