Product Description

The SQ6309 is a single-stage fly-back type constant current PWM controller with active high power factor correction and high-precision primary side regulation(PSR) feedback for full range input voltage from 85VAc~265VAc The SQ6309 detects the zero current in the secondary side and operates in boundary conduction mode.The SQ6309 provides the most cost effective solution in isolated topology without input electrolytic capacitor or optical feedback circuit from the output at the secondary side.The external high voltage MOSFET is normally in conducting condition, therefore, its switching loss can be greatly reduced. An internal cascaded low RDS(ON MOSFET is used as PWM switch to control the duty cycles.

The SQ6309 uses a unique current control method by sensing peak current from the primary side on CS pin and uses the primary and secondary winding ratio together with duty cycle to calculate the average current on the output at secondary side to achieve high precision constant output current without secondary feedback circuit; thus it saves the cost and space.

Features

• Single-stage cascade, active Power Factor  Correction(PFC),igh PF value,

       low Total Harmonic Distortion(THD)

• Constant output current with primary side control

• Short start up time(<200ms @85VAc)

• ±3% output LED current accuracy

• Operating in the boundary conduction mode(BCM)

• Natural jittering operating frequency

• Excellent line regulation

• Low start up current(< 20μA) Low operating current(< 600μA)

• Powered from auxiliary side for lower power consumption

• LED short circuit/open loop protection(SCP/OLP)

• Primary side cycle-by-cycle current limiting No input electrolytic capacitor

• Over/Under voltage protection (OVP/UVLO)

• Over temperature protection (OTP) with auto restart

• Available in SOP-8 package

• RoHS compliant and Pb free

Typical Applications

• GU10/E26/E27 LED bulb lamps

• LED PAR30/PAR38 lamps

• T5/T8 LED light tubes

• External power supply for LED lights