16 channel 50mA buck led driver
1 min read
Linear Technology has announced the LT3745, a 16 channel led driver integrated with a 55V step down controller.
According to Linear, the 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 applications such as large led billboards. Each channel has individual 6bit dot correction current adjustment and 12bit greyscale PWM dimming. Combined with a 0.5µs minimum led on time, the LT3745 is designed to offer wide dynamic contrast ratios. Both dot correction and greyscale dimming are accessible via a serial interface in TTL/cmos logic. The LT3745's 6 to 55V input voltage range is suitable for input sources found in commercial and industrial designs, typically between 12 and 48V. Linear claims the combination of minimal externals and a 6 x 6mm QFN package provide a highly compact solution footprint for multichannel led applications.
The LT3745's internal buck controller generates an adaptive bus voltage slightly higher than the parallel led strings to deliver efficiencies over 90%. Sixteen individual linear current sinks regulate and modulate individual led strings.
The device performs full diagnostics and protection against open/short led and overtemperature faults, with the fault status sent via the serial data interface. The 30MHz fully buffered, skew balanced, cascadable serial interface makes the LT3745 suitable for large screen lcd dynamic backlighting as well as full colour led displays.
The LT3745EUJ is available in a 40lead 6 x 6mm QFN package.