Analog Devices Inc. LTC3871 Bidirectional PolyPhase® Synchronous Controllers are high-performance 100V/30V bidirectional two-phase controllers capable of operating in either buck or boost mode on demand. Depending on the control signal, LTC3871 regulates in buck mode from VHIGH-to-VLOW and boost mode from VLOW-to-VHIGH. These regulation capabilities make the LTC3871 controllers ideal for automotive dual battery systems. The controllers regulate the maximum current delivered in either direction through an accurate current programming loop. The current programming loop allows the two batteries to supply energy to the load simultaneously by converting energy from one battery to the other. Using a proprietary constant-frequency, current-mode architecture, the LTC3871 enhances the signal-to-noise ratio. This enhanced signal-to-noise ratio enables low-noise operation and delivers excellent current matching between phases. Additional features of the LTC3871 include continuous or discontinuous operation, OV/UV monitors, accurate output current monitoring, independent loop compensation for buck and boost operation, and overcurrent protection.