Demonstration circuit 850A is a Boost LED Driver featuring the LTC3783 a boost/SEPIC/flyback LED driver controller. The demo board requires a 3V to 14.4V input and provides 360mA LED current at up to 25V. It incorporates an output overvoltage protection feature to limit output voltage to less than 27V if the LED string is inadvertently disconnected. The LT3783 features 1000:1 PWM dimming for brightness control and analog dimming control.

The LT3491 is a fixed frequency step-up DC/DC converter specifically designed to drive up to six white LEDs in series from a Li-Ion cell. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. The device features a unique high side LED current sense that enables the part to function as a ?one wire current source;? one side of the LED string can be returned to ground anywhere, allowing a simpler one wire LED connection. Traditional LED drivers use a grounded resistor to sense LED current, requiring a 2-wire connection to the LED string.The 2.3MHz switching frequency allows the use of tiny inductors and capacitors. A single pin performs both shutdown and accurate LED dimming control. Few external components are needed: open-LED protection and the Schottky diode are all contained inside the tiny SC70 package. With such a high level of integration, the LT3491 provides a high efficiency LED driver solution in the smallest of spaces.Applications Cellular Phones PDAs, Handheld Computers Digital Cameras MP3 Players GPS Receivers

Demonstration circuit DC915 features the LT3466-1 high efficiency boost white LED driver and a step-up converter. There is one LED driver output for 6 or 8 WLEDs and a separate DC/DC converter that generates outputs for the LCD bias. VO1 drives 8 LEDs in series with 15mA LED current and VO2/VO3 can delivery ±15V at 10mA current. If the charge-pump circuitry which generates VO3 is removed (C4, C5 and D1), VO2 can deliver over 35mA of current. The input voltage range is 3V to 14V, but can go as low as 2.7V with slightly reduced output current.

The LT3478/LT3478-1 are 4.5A step-up DC/DC converters designed to drive LEDs with a constant current over a wide programmable range. Series connection of the LEDs provides identical LED currents for uniform brightness without the need for ballast resistors and expensive factory calibration.The LT3478-1 reduces external component count and cost by integrating the LED current sense resistor. The LT3478 uses an external sense resistor to extend the maximum programmable LED current beyond 1A and also to achieve greater accuracy when programming low LED currents. Operating frequency can be set with an external resistor from 200kHz up to 2.25MHz. Unique circuitry allows a PWM dimming range up to 3000:1 while maintaining constant LED color. The LT3478/LT3478-1 are ideal for high power LED driver applications such as automotive TFT LCD backlights, courtesy lighting and heads-up displays. One of two CTRL pins can be used to program maximum LED current. The other CTRL pin can be used to program a reduction in maximum LED current vs temperature to maximize LED usage and improve reliability.Additional features include inrush current protection, programmable open LED protection and programmable soft-start. Each part is available in a 16-pin thermally enhanced TSSOP Package.Applications High Power LED Driver Automotive Lighting

Demonstration circuit 986 is a Triple Step-Down LED Driver featuring the LT3496EUFD. The LT3496 is a triple output DC/DC converter designed to operate as current sources for driving high current LEDs. Each ofthe three regulators on the demo board is independently operated. The default current for each output channel is 500mA. The output current should not exceed the rated current of the LEDs used.  The maximum voltage of an LED string the demo board can drive is limited by the duty cycle and the input voltage of the LT3496. The maximum power input voltage (PVIN ) is 45V. As a result, each channel of the demo board can drive up to ~31V total LED voltage. The LT3496's input voltage range is 3V to 30V (with 40V transients), however to minimize power dissipation the demo board uses a 3V to 5.5V supply.

EVALUATION KIT, LINEAR, LED DRIVER;

EVALUATION KIT, 800KHZ, 2.7V-5.5V, 10MA;

EVALUATION KIT, LED DRIVER;

Laser Drivers 3.2Gbps SFP VCSEL w/Diagnostic Mtr

The ADP8860SHIELD-EVALZ and the ADP8861SHIELD-EVALZ incorporate light emitting diodes (LEDs) for quick and easy evaluation of the ADP8860 and the ADP8861. Note that only the ADP8860SHIELD-EVALZ has dual light intensity sensors. The ADP8860SHIELD-EVALZ and the ADP8861SHIELD-EVALZ follow the form factor of a regular Arduino® shield to allow compatibility with microcontroller boards that use the same interface. These evaluation boards also incorporate a separate header dedicated to I2C communications. The ADP8860 and the ADP8861 are 7-channel LED drivers that utilizes a charge pump with selective gain for maximum efficiency. The LEDs driven by either device are programmable for maximum current and fade in and out times via the I2C interface. Only the ADP8860 has a programable light intensity threshold that can be set via the I2C interface of the device. Each channel can handle up to 30 mA (typical), except for the seventh channel, which can handle 60 mA (typical). Each channel can be unified to have the same fade in time and fade out time, or each channel can have an individual fade in time and fade out time for greater flexibility. For full details on the ADP8860 and the ADP8861, see the ADP8860 and the ADP8861 data sheets, which should be consulted in conjunction with the user guide when using these evaluation boards.