PowerIntLNK407EG15WLED驱动方案(DER278)
2011-06-24
PowerInt公司的LNK403-409EG/413-419EG LinkSwitch-PH系列是LED驱动器,具有PF>0.9,TRIAC调光兼容(LNK403-409)和高效率,单级PF和恒流控制器不需要PFC和电解电容等无源元件.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,逐个周期限流和滞后热关断电路,主要用在离线LED驱动器.本文介绍了LinkSwitch-PH系列主要特性, 方框图, 典型应用电路图, 通用输入7W和14W LED驱动器方框图,以及采用LNK407EG的无电解电容高效(大于90%),高功率因素(大于0.9) 15W LED驱动器参考设计主要特性,电路图,材料清单.
LNK403-409EG/413-419EG LinkSwitch-PH Family
LED Driver IC, Single-Stage PFC, Primary-Side Constant Current Control and TRIAC Dimming/Non-Dimming Device Options
The LinkSwitch-PH dramatically simplifies implementation of LED drivers requiring PF >0.9, TRIAC dimmer capability (LNK403-409) and high efficiency. The single-stage PF and constant current controller eliminates passive circuitry required for power factor correction and electrolytic bulk capacitor. The advanced primary-side control techniques used by the LinkSwitch-PH device provide accurate constant current control while eliminating the need for an optocoupler and secondary-side current control circuitry.
LinkSwitch-PH incorporates a 725 V 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, all in a monolithic IC.
LinkSwitch-PH系列主要特性:
Dramatically Simplifies Off-line LED Drivers
• LNK403-409 family is optimized for flicker-free operation in TRIAC dimming applications
• 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, >85% achievable 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系列典型应用电路图
图3. LinkSwitch-PH系列隔离TRIAC调光通用输入14W LED驱动器方框图
图4. LinkSwitch-PH系列隔离无调光通用输入7W LED驱动器方框图
DER278参考设计:采用LNK407EG的无电解电容高效(大于90%),高功率因素(大于0.9) 15W LED驱动器
This document describes an isolated, power factor corrected, very high efficiency
LED driver designed to drive an LED string of 30 V at a current of 500 mA (both nominal)
from an input voltage range of 90 to 265 VAC.
The LED driver uses a LNK407EG 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.
This document contains the LED driver specification, schematic, bill of material,transformer documentation and typical performance characteristics. The design was based on the reference design board RD-194 with simple component changes to meet the new specification.
DER278参考设计主要特性:
No electrolytic capacitors
Clean monotonic start-up – no output blinking
Fast start-up (<100 ms) – no perceptible delay
Highly energy efficient
o ≥90% at 230 VAC 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
DER278参考设计主要指标:
图5.15W LED驱动器DER278参考设计外形图
图6.15W LED驱动器DER278参考设计电路图
15W LED驱动器DER278参考设计材料清单(BOM):
图7.变压器电路图
变压器电指标:
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/der278.pdf