Bridging 12 V and 48 V in dual-battery automotive systems

The 12 V lead-acid battery system has met its match. With increasingly strict emission regulations, growing power load requirements of advanced automotive electronics and the conversion from mechanical components to electronic functions, the traditional automotive battery of choice has reached its current-carrying capacity.

In response, automakers and their suppliers have developed a second, additional electrical system at 48 V which delivers more power at lower currents than a traditional 12-V battery can produce alone.

In the white paper, Bridging 12 V and 48 V in dual-battery automotive systems, I explain how a bidirectional buck-boost controller helps support a dual-bus topology. 

You can also go straight to the reference design, Bidirectional DC-DC Converter Reference Design for 12-V/48-V Automotive Systems

  • TI brought Detroit to the Middle East region.  As I'm from Karachi, Pakistan interested in Integration of the 12 Volt to the Hybrid, or EV.  As per announcement from Akio Toyoda President Toyota Motor Corporation Toyota has provided free access to patents on the Hybrid autos, cars worldwide.  This has opened several chapters for a developing country as Pakistan with no manufacturing industry.  Simply a screw driver industry for assembly of CKD to a car.  I seek your assistance how we can use TI 48 Volt model for conversion of the autos., to EV/Hybrid from diesel, or gasoline, to environment friendly.   Please email:  with complete information will be highly appreciated. Best wishes,

  • Dear Rashid,

    thank you for your interest in our solutions. Please note that Texas Instruments is a semiconductor manufacturer only. We do not offer complete system solutions for OEMs like TIER1 suppliers. We highlight the performance of our integrated circuits through reference designs (, evaluation modules or demos. We are happy to assist you with the electronics design on the circuit level. Seek for E2E forum ( for further assistance.

    Best Regards, Jiri Panacek