Copyright@Winsemi Microelectronics Co., Ltd., All right reserved.

WINSEMI MICROELECTRONICS

WINSEMI MICROELECTRONICS

WINSEMI MICROELECTRONICS

WINSEMI MICROELECTRONICS

WINSEMI MICROELECTRONICS

0318

Features



Critical Conduction Mode Operation



Internal 500V Power MOSFET



Gate Drive and No Auxiliary Winding



±

3% LED Current Accuracy



Efficiency up to 93%



LED Short Circuit Protection



LED Open Circuit Protection



Current Sense Resistor Short Protection



Thermal Regulation Function

Applications



LED Bulb Lights



LED Panel Lights



LED Strings

Description

The WS9441 is a high precision buck constant current LED

driver and is applied to non-isolated buck LED power system with

AC input voltage of 85VAC-265VAC. The WS9441 integrates a

500V power MOSFET, and can achieve excellent constant current

performance with very few external components, so the system

cost and size are minimized. The driver operates in critical

conduction mode, and the output current does not change with the

inductance and LED output voltage. The operating current of the

IC is 200uA, so it doesn’t need the auxiliary winding for supplying

the chip, thus simplifying design and reducing cost.

The WS9441 adopts intelligent temperature control and

thoroughly solves the problem of light flashing at high

temperatures. The WS9441 offers full protection functions to

improve the system reliability, including LED open circuit

protection, LED short circuit protection, CS resistor short circuit

protection and thermal regulation function.

The WS9441 is available in SOP-7 Package.

Typical Application Circuit

Non-isolated BuckOffline LED Driver