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 ADD5211 is a four-string, white LED driver for backlight applications based on high efficiency, current mode, step-up converter technology. The boost controller drives an external MOSFET switch for step-up regulation from an input voltage of 4.5 V to 40 V and a pin adjustable operating frequency from 200 kHz to 1.2 MHz. An adjustable UVLO function is implemented to reduce input current during power-off.The ADD5211 provides four regulated current sinks for uniform brightness intensity. Each current sink can be driven from 40 mA to 200 mA; the LED driving current is pin adjustable using an external resistor. With an input PWM interface, the ADD5211 drives up to four parallel strings of multiple series connected LEDs.Additional features include LED short protection, LED open protection, boost output short protection, overvoltage protection, cycle-by-cycle current limit, and thermal shutdown for both the IC and the LED array. An open-drain fault output is also included. A programmable soft start is implemented to reduce inrush current during startup. Applications LCD monitor and TV LED backlights Industrial lighting

3A, Full Featured DC/DC Converter with Soft-Start and Inrush Current Protection Features: Wide Input Voltage Range: 2.5V to 24V 3A, 42V Internal Switch High Efficiency Power Conversion: Up to 89% Soft-Start Frequency Set by External Resistor: 200kHz to 3.5MHz Protection Against Input Short Circuits and Hot Plugging Low VCESAT Switch: 0.3V at 2.5A (Typical) Capable of Positive and Negative Outputs Available in Thermally Enhanced 14-Lead (4mm × 3mm) DFN and 16-Lead TSSOP Packages

PWM LED Driver and Boost, Flyback and SEPIC Controller Features: True Color PWM™ Delivers Constant Color with 3000:1 Dimming Ratio Fully Integrated Load FET Driver for PWM Dimming Control of High Power LEDs 100:1 Dimming from Analog Inputs Wide FB Voltage Range: 0V to 1.23V Constant Current or Constant Voltage Regulation Low Shutdown Current: IQ = 20μA 1% 1.23V Internal Voltage Reference 2% RUN Pin Threshold with 100mV Hysteresis Programmable Operating Frequency (20kHz to 1MHz) with One External Resistor Synchronizable to an External Clock Up to 1.3fOSC Internal 7V Low Dropout Voltage Regulator Programmable Output Overvoltage Protection Programmable Soft-Start Can be Used in a No RSENSE™ Mode for VDS < 36V 16-Lead DFN and TSSOP Packages

36V, 1A Module (Power Module) LED Driver and Current Source Features: True Color PWM™ Delivers Constant Color with 250:1 Dimming Ratio Wide Input Range: 4V to 36V Up to 1A LED Current Adjustable Control of LED Current High Output Current Accuracy is Maintained Over a Wide Range from 35mA to 1A Open LED and Short-Circuit Protection Grounded LED Cathode Connection Small Footprint (15mm × 9mm × 4.32mm) Surface Mount LGA Package

LIGHTING DEVELOPMENT KITS;

LED Lighting Development Tools LT3791 4.7V-60V input to drive 25V of LEDs at 2A (scaleable to 100W)

The ADN2871 laser diode driver (LDD) is designed for advanced SFP and SFF modules, using SFF-8472 digital diagnostics. The ADN2871 supports operation from 50 Mbps up to 4.25 Gbps.Average power and extinction ratios can be set with a voltage provided by a microcontroller DAC or by a trimmable resistor or digital potentiometer. The average power control loop is implemented using feedback from a monitor photodiode. The device provides bias and modulation current monitoring, as well as fail alarms and automatic laser shutdown (ALS). The device interfaces easily with the Analog Devices, Inc., ADuC7019 and ADuC7020 family of MicroConverter® devices and with the ADN2890, ADN2891, and ADN2892 family of limiting amplifiers to make a complete SFP/SFF transceiver solution. An SFP reference design isavailable.The product is pin-compatible with the ADN2870 dual-loop LDD, allowing the same design to work with either device. For dual-loop control applications, refer to the ADN2870 data sheet. The product is available in a space-saving 4 mm × 4 mm LFCSP specified over the −40°C to +85°C temperature range.Applications 1×/2×/4× Fibre Channel SFP/SFF modules Multirate OC3 to OC48-FEC SFP/SFF modules LX-4 modules DWDM/CWDM SFP modules 1GE SFP/SFF transceiver modules VCSEL, DFB, and FP transmitters

The LT3003 drives three separate strings of LEDs up to 350mA/channel with 3% accurate current matching, resulting in uniform LED brightness and intensity. This approach is superior to conventional methods of running three separate channels with external ballast resistors requiring expensive factory calibration.The LT3003 operates in boost, buck and buck-boost mode. A True Color PWM Dimming ratio of up to 3000:1 is achievable using a logic-level signal at the PWM pin for all modes without the need for external level-shifting circuitry. For applications with input supply above and below the output voltage of the LED strings, the LT3003 allows the LEDs to be returned to the input supply (buck-boost mode) instead of being limited to only SEPIC solutions.The LT3003 is ideal for high power LED driver applications such as TFT LCD backlighting and heads-up displays. Additional overtemperature outputs allow appropriate system management for increased reliability.The LT3003 is available in a small 10-pin MSE package.Applications High Power LED Ballaster Automotive Lighting Video Cameras TFT LCD Backlighting

EVALUATION KIT, LED DRIVER;