Toshiba Launches Automotive MCUs for Electronic Control Units Compliant with Functional Safety Standards

The ISO 26262, a functional safety standard for automotive electronic control units, is likely to be published within 2011. Once it is published, fail-safe functions will have to be incorporated in microcontrollers, which are the principal components of electronic control units, to ensure safe control even in the event of failure of certain functions. The market for microcontrollers compliant with functional safety standards is expected to grow rapidly and is forecast to be worth 100 billion yen in fiscal 2015.

Toshiba’s functional safety microcontrollers employ the “single-core tightly coupled method” whose CPU core has a dedicated monitoring circuit. Technology licensed from YOGITECH S.p.A. of Italy is applied to part of the monitoring circuit. Unlike the conventional “dual-core lock step method”, the single-core tightly coupled method, with the built-in monitoring circuit, achieves immediate detection of internal system failure and can accurately narrow down the location of the failure. Therefore, Toshiba’s microcontrollers are ideal for use in the development of fail-operational electronic control systems capable of maintaining operation of a vehicle with the minimum functions in the event of failure.

The TMPM350FDTFG, incorporating Toshiba’s original programmable motor driver, excitation signal output circuit for resolvers, AD converters, etc., is ideal for applications like electric power steering, as more precise control is made possible through enhancement of the accuracy of external signal input from the motor and higher resolution of output signal.

The TMPM354F10TFG, used mainly for control of drive motors, incorporates an on-chip resolver to digital converter that converts signals from the motor resolver to digital data, resulting in a smaller footprint. Whereas conventional models applied only to rotation position sensors using excitation signals like resolver, the more versatile new product is also applicable to rotation position sensors that do not use excitation signals by correcting sensor input signals. Moreover, it reduces CPU operation cycles by more than 50% by having the hardware engine perform basic vector control operations of the motor, which were previously performed by software.

Toshiba intends to win a larger share of the global microcontroller market by expanding the line-up of products compliant with functional safety standards. Toshiba’s sales target for microcontrollers compliant with functional safety standards is 10 billion yen in fiscal 2015.