IS32LT3957A
DESCRIPTION
The IS32LT3957A 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 100k Hz~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.
The IS32LT3957A integrates circuity to detect output open/short, RT/SYNC pin short, VDD short, VCC under voltage lockout and over temperature fault conditions. These failure conditions can be reported by the open drain fault reporting FAULTB pin.
An MCU can...
