GENERAL DESCRIPTION

OB3335A is a TRIAC dimmable high power factor, low THD, highly integrated buck-boost/flyback regulator with advanced features to provide high efficiency control and high precision constant current output for dimmable LED lighting applications.

Without external large compensation capacitor, the system can achieve high power factor and low THD with proprietary PFC control scheme.

OB3335A offers comprehensive protection coverage with auto-recovery features including LED open loop protection, LED short circuit protection, cycle-by-cycle current limiting, built-in leading edge blanking, VDD under voltage lockout (UVLO), thermal foldback etc.

OB3335A is offered in SOP-8 package.

FEATURES

n Excellent TRIAC dimming performance

n Low system cost and high efficiency

n Without external power supply circuit

n High PF（PF>0.9）@90~132Vac input

n Low THD（THD＜10%）@90~132Vac input

n NEMA SSL6 Dimming Curve compliant

n High precision constant current regulation at universal AC input

n Quasi-Resonant operation

n Thermal foldback function for LED output current control and Over temperature protection (OTP)

n LED short circuit protection

n LED open loop protection

n Cycle-by-cycle current limiting

n Built-in leading edge blanking (LEB)

n VDD under voltage lockout with hysteresis

APPLICATIONS

n Dimmable LED lighting

Typical Application for Buck-boost topology