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WS3255 Product Description
High Precision Primary-Side Off-line PWM Power Switch
Features � 5uA ultra-low startup current � 2mA Low operating current � ±5% Constant Voltage Regulation at Universal AC
input
� Primary-side Sensing and Regulation Without TL431
and Opto-coupler
� Programmable CV and CC Regulation � Built-in Primary winding inductance compensation � Programmable cable drop compensation � Built-in soft start � Built-in Leading-edge blanking � Cycle by cycle over current protection (OCP) � VCC over voltage clamp & under voltage
lockout( UVLO)
� Maximum Gate output voltage clamped at 12V � Frequency jittering � Ultra low standby power (<100mW)
WS3255 operates in primary-side sensing and regulation. Consequently, optocoupler and TL431 could be eliminated, thus reduce the cost.