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

 

Structure Type		Part No.	MOS	Package	App. Watt		OVP	PDF
					176-264Vac	90-264Vac
Non-isolation	PF﹥0.5	WS9441	1A/500V	SOP7	80V/220mA	80V/150mA	External Set
					150V/150mA

 

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.