In this thesis, we examine the reliability of the electronic part of the third brake light, based on
the reliability of individual electronic components on the electronic circuit. The component system has the function of the automotive third brake light, which is very important in terms of road safety and so is its reliability.
Since the requirements for the reliability of the product at the time of use are already defined at the time of development, when there are no real data from the user database and test results, the reliability should be calculated with applying one of the applicable standards that determine the appropriate equations and correction conditions.
The introductory chapter briefly outlines the importance of reliability in electronics and which
standards are used to calculate it.
The significance of environmental conditions is also presented in the Siemens SN 29500 standard used, which is summarized in accordance with IEC 60721-3-1, and
simulation tool, based on which the values of voltage, current and power are obtained and
are necessary for calculating the rate of failure.
In the next chapter the reliability function and related time concepts are presented. In this chapter, we find the degree of failure rate over component lifetime and description of its periods.
Above all, the second period is important, that is the period of normal use, where a constant failure rate is predicted and when the considered system reliability calculations apply.
In the third chapter, some of the main methods for predicting component failure rates are outlined, following a detailed presentation of the used SN 29500 standard and failure rate influence factors, which are covered by calculations in the standard.
The fourth chapter describes the bill of material of electronic circuit of the third brake light.
It also covers the operation requirements or the anticipated load on the entire system as well as individual components. The load factor is highlighted, which is extremely important when calculating the failure rate of components of the third brake light, as it is not constantly loaded, but only in the event of a car braking.
In the next, chapter five, are detailed calculations of the failure rate degree of individual system components with respect to influential or dependent factors. With calculations, correction from the reference values prescribed by the standard are made to the actual ones, taking into account the loads and the conditions in the fourth chapter.
The sixth chapter outlines the difference between serial and parallel circuit. The use of tables and graphs shows the contribution failure rates of individual components and
of the entire electronic circuit. Calculated times between failures and reliability of electronic system are displayed, for which the equations of the serial circuit were taken into account. In the last, seventh chapter, we address the conclusions and the subjective opinion on the standard used and the calculation of the reliability of the components.
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