Analog Devices Inc./Maxim Integrated

The LT3762 is a synchronous DC/DC controller designed to operate as a constant-current source and constant-voltage regulator. It features a programmable internal PWM dimming signal generator and a synchronous gate driver. The LT3762 is ideally suited for driving high current LEDs with high efficiency and reduced power loss. Rail-to-rail switch current sensing enables synchronous boost topologies and nonsynchronous topologies such as SEPIC. A voltage feedback pin serves as the input for several LED protection features and also allows the converter to operate as a constant-voltage source.A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance and external component size. Adding a capacitor at SSFM pin activates the Spread-Spectrum Modulation feature to reduce EMI. The LT3762 also includes an integrated DC/DC converter to efficiently produce a regulated 7.5V supply for the N-channel MOSFET gate drivers. The PWM pin controls PWMTG to drive the P-channel MOSFET, allowing a high PWM dimming range (3000:1) and providing LED overcurrent protection and short-circuit protected boost capability.ApplicationsIndustrial and Automotive LightingAccurate Current-Limited Voltage Regulators

The LT3763 is a fixed frequency, synchronous, step-down DC/DC controller designed to accurately regulate output currents up to 20A. The average current mode controller will maintain inductor current regulation over a wide output voltage range from 0V to 55V. Output current is set by analog voltages on the CTRL pins and an external sense resistor. Voltage regulation and overvoltage protection are set with a voltage divider from the output to the FB pin. The switching frequency is programmable from 200kHz to 1MHz through an external resistor on the RT pin or with the SYNC pin and an external clock signal. Input and output current sensing provides input current limiting and an accurate measurement of these currents. The FBIN pin is provided for applications requiring a peak power tracking function.Additional features include an accurate external reference voltage for use with the CTRL pins, an accurate UVLO/EN pin that allows for programmable UVLO hysteresis, a PWM driver for LED applications, output voltage fault detection, and thermal shutdown.ApplicationsHigh Power Architectural LightingAutomotive LightingAviation and Marine Strobe LightsSolar-Powered Chargers, Laser Diodes

The LT3781 controller simplifies the design of high power synchronous dual transistor forward DC/DC converters. The part employs fixed frequency current mode control and supports both isolated and nonisolated topologies. The IC drives external N-channel power MOSFETs and operates with input voltages up to 72V.The LT3781 is ideal for output derived power schemes, through the use of a large undervoltage lockout hysteresis range. The part is also equipped with an 18V VCCshunt regulator, which prevents exceeding absolute maximum ratings while in trickle start applications.The LT3781’s operating frequency is programmable and can be synchronized up to 350kHz. Switch phase is also controlled during synchronized operation to accommodate multiple-converter systems. Internal logic guarantees 50% maximum duty cycle operation to prevent transformer saturation.The LT3781 is available in a 20-lead SSOP package.ApplicationsIsolated Telecommunication SystemsPersonal Computers and PeripheralsDistributed Power Step-Down ConvertersLead Acid Battery Backup SystemsAutomotive and Heavy Equipment

The LT3782A is a current mode 2-phase step-up DC/DC converter controller. Its high switching frequency (up to 500kHz) and 2-phase operation reduce system filtering capacitance and inductance requirements.With 10V gate drive (VCC≥13V) and 4A peak drive current, the LT3782A can drive most industrial grade high power MOSFETs with high efficiency. For synchronous applications, the LT3782A provides synchronous gate signals with programmable falling edge delay to avoid cross conduction when using external MOSFET drivers. Other features include programmable undervoltage lockout, soft-start, current limit, duty cycle clamp (50% or higher) and slope compensation. The LT3782A is identical to the LT3782 except that the LT3782A has a tighter current sense mismatch tolerance.The LT3782A is available in thermally enhanced 28-lead TSSOP and 4mm × 5mm QFN packages.ApplicationsIndustrial EquipmentTelecom InfrastructureInterleaved Isolated Power Supply

The LT3790 is a synchronous 4-switch buck-boost voltage/current regulator controller. The LT3790 can regulate output voltage, output current, or input current with input voltages above, below, or equal to the output voltage. The constant-frequency, current mode architecture allows its frequency to be adjusted or synchronized from 200kHz to 700kHz. No top FET refresh switching cycle is needed in buck or boost operation. With 60V input, 60V output capability and seamless transitions between operating regions, the LT3790 is ideal for voltage regulator, battery/super-capacitor charger applications in automotive, industrial, telecom, and even battery-powered systems.The LT3790 provides input current monitor, output current monitor, and various status flags, such as C/10 charge termination and shorted output flag.APPLICATIONSAutomotive, Telecom, Industrial SystemsHigh Power Battery-Powered System