HIGH PRECISION NON-ISOLATED POWER SWITCH

DESCRIPTION

USL250X offers comprehensive protection coverage with auto-recovery features including LED string short circuit protection, cycle-by-cycle current limiting, built-in leading edge blanking, VDD under voltage lockout (UVLO), over temperature protection(OTP), etc. Cycle-by-Cycle current limiting is offered in USL250X. The switch current is detected by a sense resistor into the CS pin. An internal leading edge blanking circuit chops off the sensed voltage spike at initial power MOSFET on state so that the external RC filtering on sense input is no longer needed. It is a high current precision, non-isolated power switch for LED lighting. It works under transition mode. 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 Rs at CS pin and high precision constant current regulation is realized.

FEATURES

* High precision constant current regulation at universal AC input

* Support system application with PF>0.7 and no flicking

* Sense and supply without auxiliary winding inductance

* Low system cost and high efficiency

* Low operation current

* Programmable CC regulation

* Transition mode operation

* LED string short circuit protection

* Cycle-by-Cycle current limiting

* Built-in Leading Edge Blanking (LEB)

* VDD Under Voltage Lockout with Hysteresis

* Over temperature protection (OTP)