Offering bidirectional voltage or current regulation and bidirectional reverse current protection, the LT8228 and LTC7871 controllers provide a simple, reliable power solution for dual-battery automotive and industrial systems.
The Analog Devices LT8228, available from Mouser Electronics, is a single-phase controller that offers a stable power solution for 48 V and 12 V dual-battery systems in automobiles, in which the 12 V bus powers the lighting, infotainment, and audio systems, while the 48 V bus powers active chassis systems, air conditioning compressors, and other performance systems. The device is a 100 V constant-voltage or constant-current synchronous buck or boost controller, with the direction of power flow determined automatically by the LT8228 itself or controlled externally. The controller features input and output protection MOSFETs to control inrush currents, guard against negative voltages, and provide isolation between terminals under fault conditions. The controller is also an ideal option for power interruption protection systems, high-power system backup and stabilisation, and “N+1” redundant, high-reliability power supplies.
The LTC7871 is a six-phase bidirectional switching regulator controller that operates in either buck or boost mode on demand via control signal, making it ideal for automotive 48 V and 12 V dual-battery systems as well. The LTC7871 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 providing excellent current matching between phases. Additional features include an SPI-compliant serial interface, discontinuous or continuous mode of operation, overvoltage and undervoltage monitors, independent loop compensation for buck and boost operation, accurate inductor current monitoring, and overcurrent protection.
For evaluation, Mouser also stocks the Analog Devices LT8228 demo circuit DC2351A, designed to have 36V to 54V on one side and 8V to 14V on the other side. The circuit can supply a 35A maximum output current in buck mode while delivering 7A of current in boost mode. The DC2351A demo circuit can be paralleled with other DC2351A boards, enabling increased output current with adequate airflow or heatsinking.