AL3353S-13

The AL3353 is a highly integrated and cost-effective light-emitting diode (LED) controller, optimized for backlighting applications in liquid crystal display (LCD) monitors and LCD TVs. It offers a high-performance LED backlighting solution with low bill-of-materials costs. The chip incorporates a PWM boost driver, which uses current-mode control and fixed-frequency operation to regulate the LED current. The LED current is sensed through an external current-sensing resistor, and the voltage across the sensing resistor is compared with a 400mV reference level. The error is amplified to control the pulse width of the power switch, thereby regulating the current flowing through the LEDs. The AL3353 provides a PWM-to-analog dimming mode, suitable for a wide dimming control range. It features comprehensive protection functions, including overcurrent protection (OCP) for the power MOSFET, overvoltage protection (OVP) for the output, short-circuit protection for the diode and inductor, short-circuit protection for the LED cathode to ground, undervoltage lockout (UVLO) for the IC power supply, open-LED protection, short-circuit protection for VOUT, and over-temperature protection (OTP). The AL3353 is available in a lead-free SO-8 (Type TH2) package.