GENERAL DESCRIPTION

OB3605Ax is a high current precision, non-isolated power switch for LED lighting. It works under transition mode.

It significantly simplifies the LED lighting system design by eliminating the auxiliary winding inductance and works under low current. A 500V power switch is also integrated into the device. The LED current can be adjusted externally by the sense resistor Rcs at CS pin and high precision constant current regulation is realized. It integrates an external dimming pin which inputs PWM signal and can dim by changing the duty cycle of the PWM signal.

OB3605Ax offers comprehensive protection coverage with auto-recovery features including LED string open protection, LED string short circuit protection,  cycle-by-cycle current limiting, built-in leading edge blanking, VDD under voltage lockout (UVLO), Thermal foldback, etc.

OB3605Ax is offered in DIP7 /SOP7package.

FEATURES

External PWM dimming

High precision Constant Current Regulation at Universal AC input

Sense and supply without auxiliary winding inductance

Low System Cost and High Efficiency

Low operation current

Programmable CC Regulation

Transition Mode operation

Built-in Primary winding inductance compensation

Programmable LED string open circuit protection

LED string short circuit protection

Cycle-by-Cycle Current Limiting

Built-in Leading Edge Blanking (LEB)

VDD Under Voltage Lockout with Hysteresis

Thermal foldback

APPLICATIONS

LED lighting

TYPICAL APPLICATION