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 LT6118 is a complete high side current sense device that incorporates a precision current sense amplifier, an integrated voltage reference and a latching comparator. The comparator latch functionality can be enabled or disabled and the comparator can be configured to reset upon power-on. The input and the open-drain output of the comparator are independent from the current sense amplifier. The comparator trip point and amplifier gain are configured with external resistors.The overall propagation delay of the LT6118 is typically only 1.4?s, allowing for quick reaction to overcurrent conditions. The 1MHz bandwidth allows the LT6118 to be used for error detection in critical applications such as motor control. The high threshold accuracy of the comparator, combined with the ability to latch the comparator, ensures the LT6118 can capture high speed events.The LT6118 is fully specified for operation from ?40?C to 125?C, making it suitable for industrial and automotive applications. The LT6118 is available in the small 8-lead MSOP and 8-lead DFN packages.Applications Overcurrent and Fault Detection Current Shunt Measurement Battery Monitoring Motor Control Automotive Monitoring and Control Industrial Control

The LTC3766 is a PolyPhase-capable secondary-side controller for synchronous forward converters. When used in conjunction with the LTC3765 active-clamp forward controller and gate driver, the part creates a complete isolated power supply that combines the power of multiphase operation with the speed of secondary-side control.The LTC3766 has been designed to simplify the design of active clamp forward converters. Working in concert with the LTC3765, the LTC3766 forms a robust, self-starting converter that eliminates the need for the separate bias regulator that is commonly used in secondary-side control applications. A precision current-limit coupled with clean start-up into a pre-biased load make the LTC3766 an excellent choice for high-power battery charger applications.The LTC3766 provides extensive remote sensing and output protection features, while Direct Flux Limit guarantees no transformer saturation without compromising transient response. A linear regulator controller and internal bypass LDO are also provided to simplify the generation of the secondary-side bias voltage.Applications Isolated 48V Telecommunication Systems Isolated Battery Chargers Automotive and Military Systems Industrial, Avionics and Heavy Equipment

The LTC3766 is a PolyPhase-capable secondary-side controller for synchronous forward converters. When used in conjunction with the LTC3765 active-clamp forward controller and gate driver, the part creates a complete isolated power supply that combines the power of multiphase operation with the speed of secondary-side control.The LTC3766 has been designed to simplify the design of active clamp forward converters. Working in concert with the LTC3765, the LTC3766 forms a robust, self-starting converter that eliminates the need for the separate bias regulator that is commonly used in secondary-side control applications. A precision current-limit coupled with clean start-up into a pre-biased load make the LTC3766 an excellent choice for high-power battery charger applications.The LTC3766 provides extensive remote sensing and output protection features, while Direct Flux Limit guarantees no transformer saturation without compromising transient response. A linear regulator controller and internal bypass LDO are also provided to simplify the generation of the secondary-side bias voltage.Applications Isolated 48V Telecommunication Systems Isolated Battery Chargers Automotive and Military Systems Industrial, Avionics and Heavy Equipment

The LTC3766 is a PolyPhase-capable secondary-side controller for synchronous forward converters. When used in conjunction with the LTC3765 active-clamp forward controller and gate driver, the part creates a complete isolated power supply that combines the power of multiphase operation with the speed of secondary-side control.The LTC3766 has been designed to simplify the design of active clamp forward converters. Working in concert with the LTC3765, the LTC3766 forms a robust, self-starting converter that eliminates the need for the separate bias regulator that is commonly used in secondary-side control applications. A precision current-limit coupled with clean start-up into a pre-biased load make the LTC3766 an excellent choice for high-power battery charger applications.The LTC3766 provides extensive remote sensing and output protection features, while Direct Flux Limit guarantees no transformer saturation without compromising transient response. A linear regulator controller and internal bypass LDO are also provided to simplify the generation of the secondary-side bias voltage.Applications Isolated 48V Telecommunication Systems Isolated Battery Chargers Automotive and Military Systems Industrial, Avionics and Heavy Equipment

The LTC2983 measures a wide variety of temperature sensors and digitally outputs the result, in ?C or ?F, with 0.1?C accuracy and 0.001?C resolution. The LTC2983 can measure the temperature of virtually all standard (type B, E, J, K, N, S, R, T) or custom thermocouples, automatically compensate for cold junction temperatures and linearize the results. The device can also measure temperature with standard 2-, 3- or 4-wire RTDs, thermistors and diodes. It has 20 reconfigurable analog inputs enabling many sensor connections and configuration options. The LTC2983 includes excitation current sources and fault detection circuitry appropriate for each type of temperature sensor.The LTC2983 allows direct interfacing to ground referenced sensors without the need for level shifters, negative supply voltages, or external amplifiers. All signals are buffered and simultaneously digitized with three high accuracy, 24-bit ?? ADCs, driven by an internal 10ppm/?C (maximum) reference.Applications Direct Thermocouple Measurements Direct RTD Measurements Direct Thermistor Measurements Custom Sensor Applications

The LTC2983 measures a wide variety of temperature sensors and digitally outputs the result, in ?C or ?F, with 0.1?C accuracy and 0.001?C resolution. The LTC2983 can measure the temperature of virtually all standard (type B, E, J, K, N, S, R, T) or custom thermocouples, automatically compensate for cold junction temperatures and linearize the results. The device can also measure temperature with standard 2-, 3- or 4-wire RTDs, thermistors and diodes. It has 20 reconfigurable analog inputs enabling many sensor connections and configuration options. The LTC2983 includes excitation current sources and fault detection circuitry appropriate for each type of temperature sensor.The LTC2983 allows direct interfacing to ground referenced sensors without the need for level shifters, negative supply voltages, or external amplifiers. All signals are buffered and simultaneously digitized with three high accuracy, 24-bit ?? ADCs, driven by an internal 10ppm/?C (maximum) reference.Applications Direct Thermocouple Measurements Direct RTD Measurements Direct Thermistor Measurements Custom Sensor Applications

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

DC847A: Demo Board for the LTC2446 24-Bit High Speed 8-Channel Delta Sigma ADCs with Selectable Multiple Reference Inputs.

The LTC4066/LTC4066-1 are USB power managers and Li-Ion battery chargers designed to work in portable battery-powered applications. The parts control the total current used by the USB peripheral for operation and battery charging. The total input current can be limited to 100mA, 500mA or ?unlimited? (i.e., above 2A). Battery charge current is automatically reduced such that the sum of the load current and the charge current does not exceed the programmed input current limit.The LTC4066/LTC4066-1 include a standalone constant-current / constant-voltage linear charger for single cell Li-ion batteries. The ?oat voltage applied to the battery is held to a tight 0.8% tolerance, and charge current is programmable using an external resistor to ground. A programmable end-of-charge status output (CHRG) indicates full charge. BAT pin charge and discharge currents can be monitored via an analog output (ISTAT). Total charge time is programmable by an external capacitor to ground. When the battery drops 100mV below the ?oat voltage, automatic recharging of the battery occurs. Also featured is an NTC thermistor input used to monitor battery temperature while charging.The LTC4066/LTC4066-1 are available in a 24-pin thin pro?le (0.75mm) 4mm x 4mm QFN package. The LTC4066 is also available in a 24-pin ultrathin pro?le (0.55mm) 4mm x 4mm UTQFN package.Applications Portable USB Devices GPS, Cameras, Broadband Wireless Modems Mulitple Input Chargers