OB3619C is a high power factor, low THD, and highly integrated buck regulator with advanced features to provide high efficiency control and high precision constant current output for LED lighting applications.


The proprietary CC control scheme is used and the system can achieve high power factor with constant on-time control scheme. Quasi-resonant (QR) operation and clamping frequency greatly improves the system efficiency. The advanced start-up technology is used to meet the start-up time requirement (<0.5s). The constant output current is compensated for tolerance of transformer inductance variation.


OB3619C 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), etc.


OB3619C is offered in SOT23-6 package.


n High PF (>0.9)

n Low THD (<15%)

n High precision constant current regulation at universal AC input

n Fast start-up (<0.5s)

n Low system cost and high efficiency

n Quasi-resonant operation

n Programmable CC regulation

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

n VDD over voltage protection

n Over temperature protection (OTP)

n Thermal fold-back control



n LED lighting