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

External PWM Dimming

 

Structure Type		Part No.	MOS	Package	App. Watt		OVP	PDF
					176-264Vac	90-264Vac
Non-isolation	PF﹥0.5	WS9442P	2A/500V	DIP7	120V/280mA	80V/300mA	External Set
					160V/220mA

 

The WS9442P 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 WS9442P 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 simplify design and reduce cost.

The WS9442P adopts intelligent temperature control and thoroughly solves the problem of LED flickering under high temperature. It integrates an external dimming pin which inputs PWM signal and can dim by changing the duty cycle of the PWM

signal. The WS9442P 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 WS9442P is available in DIP-7 Package.