500mA Wide Input Voltage Range Step-Down LED Driver with 10:1 Dimming

The LT3592 is a fixed frequency step-down DC/DC converter designed to operate as a constant-current source. An external sense resistor monitors the output current allowing accurate current regulation, ideal for driving high current LEDs. The output current can be dimmed by a factor of 10 using an external signal for nighttime brake lights.

The high switching frequency offers several advantages by permitting the use of a small inductor and small ceramic capacitors. Small components combined with the LT3592’s 10-pin DFN leadless surface mount package save space and cost versus alternative solutions. The constant switching frequency combined with low-impedance ceramic capacitors result in low, predictable output ripple.

A wide input voltage range of 3.6V to 36V makes the LT3592 useful in a variety of applications. Current mode PWM architecture provides fast transient response and cycle-by-cycle current limiting. Thermal shutdown provides additional protection.

Applications

* Automotive Signal Lighting

* Industrial Lighting

* Constant-Current, Constant Voltage Supplies

* Wide Input Voltage Range Operation from 3.6V to 36V

* Resistor Adjustable 400kHz–2.2MHz Switching Frequency

* Shorted and Open LED Protected

* Internal Switch Current Sense Resistor

* External Resistor Programs LED Current, Pin Selects 10:1 Ratio

* 50mA/500mA LED Current Settings

* Catch Diode Current Sense to Prevent Runaway at High VIN

* Small Thermally Enhanced 10-Lead DFN (2mm × 3mm) and MSOP-10 Packages