48V/12V Automotive Bidirectional Synchronous Buck or Boost DC/DC Controller Increases Available Power

摘要

Linear Technology Corp. has announce the LTC3871, a 100 V/30 V bidirectional two phase synchronous buck or boost controller, well suited for 48 V/12 V automotive dual battery systems. Current 12 V automotive systems are reaching their 3 kW power limit due to the ever-increasing demand for more electrical devices. A newly proposed standard, LV148, combines a secondary 48 V bus with the existing 12 V system. The 48 V rail includes a belt starter generator (BSG) or an integrated starter generator (ISG), a 48 V lithium-ion battery and a bidirectional DC/DC converter for delivery of up to 10 kW of available energy from the 48 V and 12 V batteries combined. This technology is targeted for conventional internal combustion automobiles, as well as hybrid electric and mild hybrid vehicles, as auto manufacturers strive to meet increasingly stringent CO2 emissions targets.