Beschreibung
The IS32LT3958 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 is the most flexible current sensing scheme, since it functions in either boost or buck-boost mode configurations. The controller can be configured with an external resistor to operate between 100kHz~1MHz frequency resulting in small external inductor and capacitors while maintaining high efficiency. A single capacitor is all that is required to set the spread spectrum dither frequency to reduce the radiated peak emission and optimize the system EMI performance.