LD7841数据手册Leadtrend中文资料规格书

描述 Description

The LD7841 is a controller targeting for isolated and non− Isolated constant voltage LED drivers. Designed to support flyback, buck-boost topologies, its proprietary voltage mode control algorithm provides near−unity power factor and tightly regulates a constant output voltage from the primary side, thus eliminating the need for a secondary side feedback circuitry or an optocoupler.

The device is highly integrated with a minimum number of external components. A robust suite of safety protection is built in to simplify the design. This device is specifically intended for very compact space efficient designs and also provides a constant voltage regulation of the output if no load is connected to the LED driver.

特性 Features

• Wide universal input range (85VAC ~ 305 VAC)
• High Voltage Startup: Start-up time : < 0.5 sec.
• Low standby power- No load power saving : < 0.2W- Standby power consumption: < 0.4W at 150mW output
• Precise CV regulation in the steady state : < ± 5 %
• CV regulation in the load transient: < ± 15%
• Total Harmonic Current Optimization : THDi < 10%
• High Power Factor : PF > 0.92
• Robust Protection Features- Brown−In/Out Detection on HV pin- AC Over Voltage Protection on HV pin- Programmable Output OVP on FB pin- Cycle−by−cycle Peak Current Limit on CS pin- Over Load Protection- Secondary Diode short Protection- Pin Short/Open Circuit Protection on CS and FB pin- Winding Short Circuit Protection on FB pin- Output Short Circuit Protection
• 250 mA / -700 mA Totem Pole Driving capability

应用 Application

• LED Driver Power Supplies
• Off Line Appliances Requiring Power Factor Correction