OB3663

On-Bright Confidential to EUCHIPS OB3663 Dimmable Flyback PSR Controller GENERAL DESCRIPTION The OB3663 is a high performance single stage AC/DC fly-back controller for dimmable LED luminaires. The OB3663 integrates advanced digital processing core to eliminate visible flicker. OB3663 offers fast startup feature, constant on-time control for power factor correction (PFC), zero current detector (ZCD) to ensure transition mode (TM) operation, and accurate current regulation. OB3663 offers comprehensive protection coverage including VDD under voltage lockout (UVLO), VDD over voltage protection, load voltage over voltage protection, cycle-by-cycle current limiting, over temperature protection, LED string open/short protection, driver output clamping for external power MOSFET protection, current sense resistor short protection, and transformer saturation protection. OB3663 is offered in SOP14 package (OB3663CP) and SSOP10 package (OB3663LP) . FEATURES  Primary-Side Control with Single Stage PFC Topology  No visible flicker  No bleeder design  Total harmonic distortion <20% with PF>0.9  Fast startup time (<0.5s without dimmer)  Transition Mode (TM) operation to achieve high efficiency  High current accuracy  Source driving operation mode  Cycle-by-Cycle Current Limiting (OCP)  VDD Over Voltage Protection  Output Over Voltage Protection  Over-Temperature Protection  VDD Under Voltage Lockout (UVLO)  LED string open protection  LED string short protection  Current ...