Home Products Power 60V, High Side Sense LED Controller for Boost, Buck or Buck-Boost High Current LED Applications

60V, High Side Sense LED Controller for Boost, Buck or Buck-Boost High Current LED Applications

Linear Technology has announced the LT3755, a 60V, high-side current sense DC/DC converter designed to drive high current LEDs. Its 4.5V to 40V input voltage range makes it ideal for a wide variety of applications, including automotive, industrial and architectural lighting. The LT3755 uses an external N-channel MOSFET and can drive up to 14 1A white LEDs from a nominal 12V input, delivering in excess of 50 watts. It incorporates a high-side current sense, enabling it to be used in boost, buck, buck-boost or SEPIC and flyback topologies. The LT3755 can deliver efficiencies of over 94% in boost mode, eliminating any need for external heat sinking. A frequency adjust pin permits the user to program the frequency between 100kHz and 1MHz, optimizing efficiency while minimizing external component size and cost. Combined with a 3mm x 3mm QFN package, the LT3755 offers a very compact 50 watt LED driver solution.

Power

11 November 2008

byNews Desk

The LT3755 uses True Color PWM™ dimming, which delivers constant LED color with dimming ranges of up to 3,000:1. For less demanding dimming requirements, the CTRL pin can be used to offer a 10:1 analog dimming range. Its fixed frequency, current mode architecture offers stable operation over a wide range of supply and output voltages. A ground referenced voltage FB pin serves as the input for several LED protection features, making it possible for the converter to operate as a constant-voltage source.

Two versions of the LT3755 are available — the standard LT3755, which offers an Open LED Status pin, and the LT3755-1, which replaces the Open LED Status pin with a frequency synchronization pin.