High-current LED driver with three-state control – VP19

Walker Bai – Applications Engineer, Section Leader, Power Products

There are many LED drivers on the market for low-current LEDs and many others for high-current LEDs. Low-current LEDs are 20mA to 100mA LEDs. High-current ones are 100mA to ∼1A. But how many 20A LED drivers do you know? How about 40A? Not many. How about super-fast µs rise time between 0A and 20A or between any two current levels? Not heard of. Not until now.

Linear Technology’s LT3743 solves the problems of driving up to 40A LEDs with super-fast 2µs PWM dimming between any current levels. It drives laser diodes too. The LT3743 does all this at 95% efficiency (12V input, 20A, 5V output) even in the low dimming range. The LT3743 can take up to 36V and can drive LEDs in series. The solution takes less than 2 square inches of PCB space.