High Efficiency, Synchronous, 4-Switch Buck-Boost Controller

The LTC3780 is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The constant frequency current mode architecture allows a phase-lockable frequency of up to 400kHz. With a wide 4V to 30V (36V maximum) input and output range and seamless transfers between operating modes, the LTC3780 is ideal for automotive, telecom and battery-powered systems.

The operating mode of the controller is determined through the FCB pin. For boost operation, the FCB mode pin can select among Burst Mode® operation, discontinuous mode and forced continuous mode. During buck operation, the FCB mode pin can select among skip-cycle mode, discontinuous mode and forced continuous mode. Burst Mode operation and skip-cycle mode provide high efficiency operation at light loads while forced continuous mode and discontinuous mode operate at a constant frequency.

Fault protection is provided by an output overvoltage comparator and internal foldback current limiting. A power good output pin indicates when the output is within 7.5% of its designed set point.

Applications

* Automotive Systems

* Telecom Systems

* DC Power Distribution Systems

* High Power Battery-Operated Devices

* Industrial Control

* Single Inductor Architecture Allows VIN Above, Below or Equal to VOUT

* Wide VIN Range: 4V to 36V Operation

* Synchronous Rectification: Up to 98% Efficiency

* Current Mode Control

* ±1% Output Voltage Accuracy: 0.8V < VOUT < 30V

* Phase-Lockable Fixed Frequency: 200kHz to 400kHz

* Power Good Output Voltage Monitor