Quad-Phase, Synchronous Bidirectional Buck or Boost Controller

The LTC7872 is a high performance bidirectional buck or boost switching regulator controller that operates in either buck or boost mode on demand. It regulates in buck mode from VHIGH-to-VLOW and boost mode from VLOW-to-VHIGH depending on a control signal, making it ideal for 48V/12V automotive dual battery systems. An accurate current programming loop regulates the maximum current that can be delivered in either direction. The LTC7872 allows both batteries to supply energy to the load simultaneously by driving energy from either battery to the other.

Its proprietary constant frequency current mode architecture enhances the signal-to-noise ratio enabling low noise operation and provides excellent current matching between phases. Additional features include an SPI-compliant serial interface, discontinuous or continuous mode of operation, OV/UV monitors, independent loop compensation for buck and boost operation, accurate inductor current monitoring and overcurrent protection.

The LTC7872 is available in a 48-lead 7mm × 7mm LXE package.

Applications

* Automotive 48V/12V Dual Battery Systems

* Backup Power Systems

* Unique Architecture Allows Dynamic Regulation of Input Voltage, Output Voltage or Current

* Operates with External Gate Drivers and MOSFETs

* VHIGH Voltages Up to 100V; VLOW Voltages Up to 60V

* Synchronous Rectification: Up to 98% Efficiency

* ADI-Proprietary Advanced Current Mode Control

* ±1% Voltage Regulation Accuracy Overtemperature

* Accurate, Programmable Inductor Current Monitoring and Bidirectional Regulation