80V Synchronous 4-Switch Buck-Boost DC/DC Controller with Bidirectional Capability

The LT8708 is a high performance buck-boost switching regulator controller that operates from an input voltage that can be above, below or equal to the output voltage. Features are included to simplify bidirectional power conversion in battery/capacitor backup systems and other applications that may need regulation of VOUT, VIN, IOUT, and/or IIN. Forward and reverse current can be monitored and limited for the input and output sides of the converter. All four current limits (forward input, reverse input, forward output and reverse output) can be set independently using four resistors on the PCB.

The MODE pin can select between discontinuous conduction mode (DCM), continuous conduction mode (CCM), hybrid conduction mode (HCM) and Burst Mode® operation. In combination with the DIR (direction) pin, the chip can be configured to process power only from VIN to VOUT or only from VOUT to VIN. With a wide 2.8V to 80V input and 1.3V to 80V output range, the LT8708 is compatible with most solar, automotive, telecom and battery-powered systems.

APPLICATIONS

* High Voltage Buck-Boost Converters

* Bidirectional Charging System

* Automotive 48V Systems

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

* Six Independent Forms of Regulation

* VIN Current (Forward and Reverse)

* VOUT Current (Forward and Reverse)

* VIN and VOUT Voltage

* Forward and Reverse Discontinuous Conduction Mode Supported

* Supports MODE and DIR Pin Changes While Switching