IS32LT3958A - Lumissil

IS32LT3958A HIGH VOLTAGE LED LIGHTING CONTROLLER

The IS32LT3958A is a current mode PWM controller designed to drive a low side external NMOS FET for wide input/output voltage range and high LED current applications. An external resistor senses the high side output current of the LED string. A high side sense resistor is the most flexible current sensing scheme, since it functions in either boost or buck-bo.

Features

two independent analog dimming pins, ICTRL and ADJR. Input DC voltage in the range of 0.06V~2V on the ICTRL pin and/or ADJR pin is required for analog dimming. PWM dimming is achieved by directly modulating the PWM/EN pin with desired PWM duty cycle or by enabling the internal PWM generator circuit. With the internal PWM generator circuit, IS32LT3958A can achieve standalone dual brightness level output. The duty cycle and frequency of the internal PWM generator is easily programmed by external resistors. The soft-start function of the IS32LT3958A has been optimized for achieving excellently sm.