The LTC3201 is an ultralow noise, constant frequency, charge pump DC/DC converter specifically designed for powering white LEDs. The part produces a low noise boosted supply capable of supplying 100mA of output current. LED current is regulated for accurate and stable backlighting. A 3-bit DAC provides output current adjust for brightness control.Low external parts count (one small flying capacitor and three small bypass capacitors) and small MSOP-10 package size make the LTC3201 ideally suited for space constrained applications. An input noise filter further reduces input noise, thus enabling direct connection to the battery. High switching frequency enables the use of small external capacitors.The LTC3201 contains overtemperature protection and can survive an indefinite output short to GND. Internal soft-start circuitry also prevents excessive inrush current on start-up. A low current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1?A.Applications White LED Backlighting Programmable Boost Current Source

DC507A: Demo Board for the LT1937 White LED Step-Up Converter in SC70 and ThinSOT.

The LTC3202 is a low noise, constant frequency charge pump DC/DC converter that uses fractional conversion to increase efficiency in white LED applications. The part can be used to produce a regulated voltage or current of up to 125mA from a 2.7V to 4.5V input. Low external parts count (two flying capacitors and two small bypass capacitors at VIN and VOUT) make the LTC3202 ideally suited for small, battery-powered applications.An internal 2-bit DAC allows LED current to be adjusted for LED brightness control. The LTC3202 also has thermal shutdown protection and can survive a continuous short-circuit from VOUT to GND. Built-in soft-start circuitry prevents excessive inrush current during start-up. High switching frequency enables the use of small external capacitors. A low current shutdown feature disconnects the load from VIN and reduces quiescent current to less than 1?A.The LTC3202 is available in the 10-pin MSOP and 3mm x 3mm DFN packages.Applications White LED Backlighting Programmable Boost Current Source?

DC805A: Demo Board for the LTC3216 1A Low Noise High Current LED Charge Pump with Independent Torch/Flash Current Control.

The LT3479 is a current mode, fixed frequency step-up DC/DC converter with an internal 3A, 42V switch. Efficiencies of up to 89% can be achieved in typical applications. It features a programmable soft-start function to limit inductor current during start-up and inrush current protection to protect the LT3479 during shorts and line transients. Both inputs of the error amplifier are available to the user allowing positive and negative output voltages. Through an external resistor, the user can program the switching frequency from 200kHz to 3.5MHz. The low profile (0.75mm) 14-pin, 4mm ? 3mm DFN package provides excellent thermal performance in a small footprint. The LT3479 is also available in a thermally enhanced 16-pin TSSOP package.Applications High Power LED Driver DSL Modems Distributed Power

DC871A-A: Demo Board for the LTC3215 700mA Low Noise High Current LED Charge Pump.

DC1947A: Demo Board for the LT3799-1 Offline Isolated Flyback LED Controller with Active PFC.

Demonstration circuit 2176A features the LT3909, a 2-string × 50mA, 2MHz step-up LED driver with ±1.8% current matching. The LT3909 precisely regulates two LED strings for equal current, supports LED dimming that reduces brightness down to a 1/40,000 ratio, protects against faults and also reports faults. The LT3909 consists of a step-up converter with a fixed 2MHz switching frequency and current sources for the LED strings. The maximum current in each LED string is 40mA. The ISET resistor can be changed to 20.0kΩ to program the string current to 50mA – see the data sheet for an application example with 50mA string current. Voltage feedback resistors optimize operation for LEDs that are 35V maximum.

The LTM8005 is a 38VIN, 38VOUT boost ?Module (powermicromodule) LED driver designed to regulate current orvoltage and is ideal for driving LEDs. The fixed frequencyand current mode architecture result in stable operationover a wide range of supply and output voltages. Spreadspectrum frequency modulation (SSFM) can be activatedfor improved electromagnetic compatibility (EMC) performance.The ground-referred voltage FB pin serves as theinput for several LED protection features, and also allows theconverter to operate as a constant voltage source. The PWMinput provides LED dimming ratios of up to 3000:1, and theCTRL inputs provide additional analog dimming capability.The low profile package enables utilization of unusedspace on the bottom of PC boards. The LTM8005 is packagedin thermally enhanced, compact over-molded BallGrid Array (BGA) package suitable for automated assemblyby standard surface mount equipment. The LTM8005is RoHS compliant.APPLICATIONS High Power LED, High Voltage LED Accurate Current-Limited Voltage Regulators

The LT3492 is a triple output DC/DC converter designed to operate as a constant-current source and is ideal for driving LEDs. The LT3492 works in buck, boost or buck-boost mode. The LT3492 uses a fixed frequency, current mode architecture resulting in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 330kHz and 2.1MHz to optimize efficiency and external component size. The external PWM input provides 3000:1 LED dimming on each channel. Each of the three channels has a built-in gate driver to drive an external LED-disconnect P-channel MOSFET, allowing high dimming range. The output current range of each channel of the LT3492 is programmed with an external sense resistor. The CTRL pin is used to adjust the LED current either for analog dimming or over-temperature protection.Applications RGB Lighting Billboards and Large Displays Automotive and Avionic Lighting Constant-Current Sources