The LT3745 from Linear Technology is a 16-channel LED driver integrated with a 55V step-down controller. The LED driver powers up to 75mA of LED current for each channel, which can drive up to 36V of LEDs in series, making it suitable for large LED billboards. Each channel has individual 6bit dot correction current adjustment and 12bit gray scale PWM dimming. Combined with a 0.5µs minimum LED on-time, the driver offers wide dynamic contrast ratios. Both dot correction and gray scale dimming are accessible via a serial interface in transistor-transistor logic and CMOS logic. The driver's 6 to 55V input voltage range is suitable for 12 to 48V input sources which is found in commercial and industrial designs. The combination of minimal externals and a 6x6mm QFN package provide a high compact solution footprint for multi-channel LED applications, claims the company.
The driver's internal buck controller generates an adaptive bus voltage. It performs full diagnostics and protection against open and short LED and over-temperature faults, with the fault status sent via the serial data interface. The 30MHz buffered, skew-balanced, cascadable serial interface makes the driver suitable for large screen LCD dynamic backlighting as well as full colour LED displays.
The LT3745EUJ is available in a 40-lead, 6x6mm QFN package and its extended temperature version the LT3745IUJ, or I-grade, is also available.
