Powerint 公司的DER206 3.7W LED驱动设计方案是采用LNK605DG器件,输入电压为90-265VAC,输出电压为10.5V/350mA. DER206设计初级采用恒压/恒流(CV/CC)控制器,从而省略了次级控制和光耦.输出电压精度±5%,输出电流精度±10%,包括火线电压,负载和温度补偿和元件误差.主要应用手机,无绳电话,PDA,MP3的充电器,适配器,LED驱动器等.本文介绍了LNK605DG的主要特性,应用案例和DER206设计电路图与材料清单.
3.7 W LED Driver Using LNK605DG:90–265 VAC Input; 10.5 V, 350 mA Output DER206设计优势:
Summary and Features
Accurate primary-side constant voltage/constant current (CV/CC) controller eliminates secondary side control and optocoupler
±5% output voltage and ±10% output current accuracy including line, load, temperature and component tolerance
No current-sense resistors for maximized efficiency
Low part-count solution for lower cost
Over-temperature protection–tight tolerance (±5%) with hysteretic recovery for safe PCB temperatures under all conditions
Auto-restart output short circuit and open-loop protection
EcoSmart – Easily meets all existing and proposed international energy efficiency standards–China (CECP) / CEC / EPA / European Commission
ON/OFF control provides constant efficiency to very light loads
No-load consumption <200 mW at 265 VAC
Ultra-low leakage current: <5 μA at 265 VAC input (no Y capacitor required)
Easy compliance to EN55015 and CISPR-22 Class B EMI
Green package: halogen free and RoHS compliant
LNK603-606/613-616 LinkSwitch-II 系列
Energy-Efficient, Accurate CV/CC Switcher for Adapters and Chargers The LinkSwitch-II dramatically simplifies low power CV/CC charger designs by eliminating an optocoupler and secondary control circuitry. The device introduces a revolutionary control technique to provide very tight output voltage and current regulation, compensating for transformer and internal parameter tolerances along with input voltage variations.
The device incorporates a 700 V power MOSFET, a novel On/Off control state machine, a high voltage switched current source for self biasing, frequency jittering, cycle-by-cycle current limit and hysteretic thermal shutdown circuitry onto a monolithic IC.
LNK603-606/613-616主要亮点:
Dramatically Simplifies CV/CC Converters
Eliminates Optocoupler and all secondary CV/CC control circuitry
Eliminates all control loop compensation circuitry
Advanced Performance Features
Compensates for transformer inductance tolerances
Compensates for input line voltage variations
Compensates for cable voltage drop (LNK61X series)
Compensates for external component temperature variations
Very tight IC parameter tolerances using proprietary trimming technology
Frequency jittering greatly reduces EMI filter cost
Even tighter output tolerances achievable with external resistor selection/trimming
Advanced Protection/Safety Features
Auto-restart protection reduces power delivered by >95% for output short circuit and control loop faults (open and shorted components)
Hysteretic thermal shutdown–automatic recovery reduces power supply returns from the field Meets HV creepage requirements between Drain and all other pins both on the PCB and at the package
EcoSmart–Energy Efficient
Easily meets all global energy efficiency regulations No-load consumption <200 mW at 230 VAC and down to below 30 mW with optional external bias On/Off control provides constant efficiency down to very light loads–ideal for CEC and ENERGY STAR 2.0 regulations No current sense resistors–maximizes efficiency
Green Package
Halogen free and RoHS compliant package
主要应用:
Chargers for cell/cordless phones, PDAs, MP3/portable audio devices, adapters, LED drivers, etc.
图1.LNK605DG方框图
图2.应用案例(输出5V/555mA)
图3.DER206设计电路图
材料清单(BOM):
