Dual synchronous step-down DC-DC controller eliminates external surge protection devices

Analog Devices has released the Power by Linear LTC7810, a high voltage non-isolated dual output synchronous step-down DC-DC controller that drives all N-channel MOSFET power stages. Its 4.5V to 140V (150V abs max) input voltage range is designed to operate from a high input voltage or from an input that has high voltage surges, eliminating the need for external surge suppression devices. The device operates at up to 100% duty cycle during input voltage dips down to 4.1V, ideal for industrial, transportation, robotic and datacom applications. The device operates with a selectable fixed frequency between 50kHz and 750kHz and is synchronizable to an external clock from 75kHz to 720kHz. The user can choose from forced continuous operation, pulse-skipping or low ripple Burst Mode operation during light loads. Its current mode architecture offers fast transient response, easy loop compensation and excellent line regulation. Current sensing is achieved by measuring the voltage drop across the output inductor (DCR) for highest efficiency or by an optional sense resistor. A low 90ns minimum on-time provides for high step-down ratios at high switching frequency. Current foldback limits MOSFET heat dissipation through overload conditions. Additional features include soft-start and adjustable input overvoltage lockout. The device is available in a 48-lead 7mm x 7mm eLQFP thermally enhanced package with no connect pins for high voltage spacing. Two operating junction temperature grades are available with extended and industrial versions from -40C to 125C and a high temp automotive version from -40C to 150C.