February 21, 2014 – Linear Technology Korea (CEO Hong Sa-kwak) announced the release of a wide-range synchronous step-down DC/DC controller (Product Name: LT3840). This product includes a 7.5V buck-boost bias voltage to provide efficient gate drive over an input voltage range of 2.5V to 60V. The LT3840 generates a 7.5V bias voltage for MOSFET gate drive regardless of whether the input voltage is higher, lower, or equal to 7.5V. The 2.5V to 60V power range is designed to protect against high-voltage transients and continuous operation during automotive cold cranking, as well as covering a variety of input sources and batteries.

The LT3840 extends operating time in battery-powered applications by dissipating only 75µA of current under no-load conditions where the output voltage is maintained. The output voltage can be set from 1.25V to 60V at output currents up to 30 amperes, resulting in a very high efficiency of 95%. These features make it highly suitable for 12V or 24V automotive, heavy equipment, industrial control, robotics, and telecommunications applications. The LT3840's precise current regulation is programmable, and a current monitor function reports the average output current. Users can select continuous operation under light load, pulse skipping, or low-ripple Burst Mode® operation.

The LT3840 features a powerful on-chip gate driver for multiple standard or logic-level N-channel MOSFETs. It operates at a selectable fixed frequency between 50 kHz and 1 MHz and can be synchronized with an external clock within the same range. This product's current mode architecture provides easy loop compensation, high-speed transient response, and excellent line regulation. Additional features include low-voltage dropout, precise overvoltage and undervoltage lockout, soft-start/tracking, and a duty cycle of up to 99% for power good signals.

The LT3840 is supplied in 28-pin TSSOP and 4mm x 6mm QFN-38 thermally enhanced packages. An extended industrial version is available from -40 to 125°C, a high-temperature automotive grade version from -40°C to 150°C, and a military grade version from -55°C to 150°C.

Photo Caption: High-voltage DC/DC synchronous controller