LT3476

The LT^®3476 is a quad output DC/DC converter designed to operate as a constant-current source for driving high current LEDs. A  xed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 200kHz and 2MHz to optimize ef ciency and external component size.

The LT3476 senses output current at the high side of the LED. High side current sensing is the most  exible scheme for driving LEDs, allowing buck, boost or buck-boost con gurations. Each current monitor threshold is trimmed to within 2.5% at the full scale of 105mV. With an external sense resistor, the user programs the output current range of each channel. Each of the four regulators is independently operated by that channelfls PWM signal.This PWM feature allows precise adjustment of the color mixing or dimming ratio of the LED source. Dimming ratios up to 1000:1 can be achieved.