摘要：  本文介绍了EVALHVLED805主要特性， 电路图和材料清单(BOM

关键字：  LED驱动器，  开关，  电流

 ST 公司的EVALHVLED805是HVLED805 PWM电流模式LED驱动器的演示板，是 4.2W离线LED驱动器.输入电压VIN从185到265 VAC，火线频率50-60Hz，最大输出功率4.2W，最大电压12V，输出电流350 mA ± 5%，正常模式的开关闭频率大于70kHz，平均效率大于70%，无负载的最大输入功率小于100W.本文介绍了EVALHVLED805主要特性， 电路图和材料清单(BOM).

 4.2 W off-line LED driver with primary side regulation

 The EVALHVLED805 is a demonstration board equipped with the new HVLED805 PWM current mode LED driver and is designed for European mains. It can control， with very good accuracy， from 1 to 3 LEDs having a nominal current of 350 mA. The HVLED805 has integrated high voltage startup and an 800 V power MOSFET. The high MOSFET’s breakdown voltage allows very robust and reliable applications and reduces the size of the snubber and the relative power dissipation. Its accurate primary-current control eliminates the need of the optocoupler which impacts the cost， the compactness and the lifetime of the application while still maintaining a very good LED accuracy (below 5 %). Moreover， this converter， specifically designed for quasiresonant (QR) flyback converters， enables very low turn-on losses and EMI emissions.

　　图1.EVALHVLED805外形图

　　EVALHVLED805主要特性:

　　■ Input voltage range (VIN): 185 - 265 VAC

　　■ Main frequency (fL): 50 - 60 Hz

　　■ Maximum (rated) output power: 4.2 W

　　■ Output: IOUT = 350 mA ± 5%

　　– Over voltage = 12 V max

　　– Current ripple < 10% IOUT

　　■ Minimum switching frequency in normal mode: 70 kHz

　　■ Target average efficiency (from 1 to 3 LEDs) > 70 %

　　■ Maximum input power in no-load < 100 mW

　　图2.EVALHVLED805电路图

　　EVALHVLED805材料清单(BOM):