Buck-boost controller efficiently transfers power between dual automotive battery systems

Texas Instruments has introduced what is claimed to be the industry's first fully integrated multiphase bidirectional DC-DC current controller, which efficiently transfers electric power greater than 500W per phase between dual 48V and 12V automotive battery systems. The highly integrated LM5170-Q1 analog controller features an innovative average current-mode control method that overcomes the challenges of today's high-component-count, full digital control schemes. The device is the latest in the company’s portfolio of industry-leading DC-DC converters, controllers and charge pumps, enabling engineers to innovate and differentiate their power supply designs. Hybrid electric vehicles use both a high-voltage 48V battery and the standard 12V automotive battery. Design engineers typically manage these dual battery systems using a digital control scheme, which includes multiple discrete components such as current-sense amplifiers, gate drivers and protection circuits. These full digital control schemes are bulky and expensive. To solve this challenge while improving performance and system reliability, the company offers a mixed architecture in which the microcontroller handles higher-level intelligent management, and the highly integrated analog controller provides the power conversion. There is a blog post available titled, "Interconnecting automotive 48V and 12V rails in dual battery systems," to learn how to overcome the challenges of designing a power supply for hybrid electric vehicles. APEC, Tampa, March 27-29, 2017, Booth 701