Study Of Functional Safety And Online Self Tests For Microcontroller

At present, functional safety has aroused general interest in the international field of safety. Functional safety standard IEC 61508 has been published to standardize design, application, management and other aspects of safety-related systems.It provides security in various fields.Nowadays, either development of safety-related products or research of technology in functional safety, is still on the initial stage in our country. From the practical application, this paper discusses the method to make the design of safety-related system meet the requirements of IEC 61508 standard, and to ensure the correct implementation of safety function. It has been proposed to use appropriate redundant archetecture and diagnostic measures in order to achieve the required safety integrity level.The completed contents in this paper are as follows:1.The diagnostic or testing measures of E/E/PE safety-related systems have been studied here. Combined with the application in automotive electronics, it mainly discusses how to make the diagnosis of the microcontroller meet the standards.2.After learning and implementing the theory of memory test, it compares the various test algorithms and selects the best one for the online self tests for micro-controller.3. The tests for CPU, variable memory, unvariable memory and the clock has been implemented, and the results are tested and verified by the experiment of fault insertion. The principle of test is applied to a variety of microcontrollers, and the program can be used as a security software library into the user program. IEC 61508 has been developed as the highest standard in the development of safety-related systems.Many industries are committed to meeting the practical requi-rements of this technical standard. Each product or system has to obtain a certification of certain safety integrity level, which is awarded by independent institutions for safety assessment such as TuV.