IS32LT3175N/P Single-Channel Linear LED Drivers ISSI IS32LT3175N/P Single-Channel Linear LED Drivers come with fade in/out and PWM dimming. The regulators serve as a stand-alone LED driver-configurable from 20mA to 150mA with external resistors, no microcontroller is necessary. A logic level “courtesy light” signal from the PWM pin can be interfaced to precisely drive the LED channel. The IS32LT3175P obtains a positive polarity PWM signal. In addition, the IS32LT3175N obtains a negative polarity PWM signal. The regulator integrates a 63-step fade-in and fades out the algorithm (Gamma correction). This causes the output LED current to increasingly rise up to the full source value after the EN pin is pulsed.