LED Driver Includes Dot Correction and Gray Scale Dimming

摘要

The LT3745 from Linear Technology is a 16-chan-nel LED driver integrated with a 55-V step-down controller. The LED driver powers up to 75 mA of LED current for each channel, which can drive up to 36 V of LEDs in series. Each channel has individual 6-bit dot correction current adjustment and 12-bit gray scale PWM dimming. Combined with a 0.5 μs minimum LED on-time, the LT3745 purportedly offers very wide dynamic contrast ratios. Both dot correction and gray scale dimming are accessible via a serial interface in TTL/CMOS logic. The LT3745's features 6-V to 55-V input voltage range. The LT3745's internal buck controller generates an adaptive bus voltage slightly higher than the parallel LED strings to deliver efficiencies over 90 percent. Sixteen individual linear current sinks regulate and modulate individual LED strings.