IS31LT3957A Overview
The IS31LT3957A 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.
IS31LT3957A Key Features
- Wide high voltage input range: 5V to 75V
- Supports boost, buck-boost, SEPIC and buck
- ±2% output current accuracy
- Programmable soft start to avoid inrush current
- Fixed under voltage lockout threshold
- EMI reduction capabilities
- Programmable spread spectrum function
- Supports either analog or PWM dimming
- Fault protection with reporting
- VCC under voltage lockout (not reported)