Advanced design ensures optimum MCU performance even during cranking
ROHM has recently announced the development of system power supplies optimized for high-performance microcontrollers in a variety of automotive systems, from electronic power steering to fuel injection, including HEVs and EVs.
The newly developed BD39001EKV-C utilizes a proprietary boost-buck switching method that ensures stable voltage supply, even when the battery voltage drops after idling stop, while improving power conversion efficiency by up to 5% vs. conventional products. And in response to the continued standardization and advancements in the automotive industry a startup sequence setting function is included that can adapt to a variety of MCU specifications and requirements.
With the continuing trend towards platform unification (standardization) in the automotive sector comes a push to promote the use of common parts worldwide. This is expected to increase demand for versatile products that can suit a variety of requirements and support microcontrollers of all types – as well as high-performance devices and solutions optimized for customized dedicated power supplies and specific applications. In addition, the need to minimize fuel consumption has led to the adoption of idling stop systems that stop the engine during idling and other brief stops in order to prevent wasteful fuel consumption. However, this requires countermeasures to prevent MCU malfunction due to battery voltage fluctuations caused by cranking after the engine starts up again. In response, ROHM quickly developed a versatile,standardized power supply IC capable of providing stable voltage after idling stop operation. The BD39001EKV-C utilizes leading-edge 0.35μm BiCDMOS power processes and takes advantage of ROHM’s analog design expertise to achieve a breakdown voltage of 40V with an ultra-low drive voltage of 4V, providing a wide input voltage range
And to ensure compatibility with idling stop systems, ROHM adopted a new boost-buck automatic switching control method that provides stable voltage (5V) to the MCU, even when the battery voltage fluctuates (below 5V), while increasingpower conversion efficiency by 5%.
Besides providing continuous, stable power supply for I/O (5V LDO) and the MCU core (3.3V DC/DC) based on a variable primary power supply, a number of surveillance functions are built in, including a window watchdog timer that monitors MCU operation, improving reliability. The products also feature a compact form factor that contributes to end-product miniaturization.