Abstract
This chapter explains the mathematics needed to perform reliability analysis and introduces the primary reliability parameters, which a development engineer must be familiar with today (Sects. 4.1 and 4.2). The so-called bathtub curve of failure rates is applied for the reliability of electronic systems; understanding the middle of this curve, which represents a constant failure rate, is critical in practice. The reliability parameters for electronic systems are easily calculated by applying this constant failure rate (Sect. 4.3). The failure modes of electronic components are described in Sect. 4.4. We show how the required reliability parameters for individual components and modules can be determined by applying the mode of constant failure rate (Sects. 4.5 and 4.6). In addition, we present how the system reliability can be calculated from the reliability of individual components. Finally, Sect. 4.7 contains recommendations for upgrading the reliability of electronic systems.
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Notes
- 1.
Calculating the failure rate for ever smaller intervals of time, i.e., the instantaneous failure rate as Δt tends to zero, results in the hazard function (also called hazard rate) , h(t). As it is a function that describes the conditional probability of failure, it is always a value between 0 and 1. (Failure rate, as the count of failures per unit time, can be a value greater than one.)
- 2.
Since MTTF can be expressed as “average life (expectancy)”, many engineers assume that 50% of items will have failed by time t = MTTF. This inaccuracy can lead to bad design decisions. Furthermore, the above statements imply the total absence of systematic failures (i.e., a constant failure rate with only intrinsic, random failures), which is not easy to verify.
- 3.
Derating is the operation of an electronic device at less than its rated maximum capability in order to prolong its life.
- 4.
The word redundancy comes from the Latin word redundare, which means available in abundance.
References
IEC 61709:2011 Electric components - Reliability - Reference conditions for failure rates and stress models for conversion, publication date 2011-06-24
Military Handbook Reliability Prediction of Electronic Equipment, MIL-HDBK-217F, 2 December 1991
MIL-R-11/RC 07/12: Electronic Components - Resistors Military Ordering Code
MIL-C-26655: Electronic Components - Capacitors Military Ordering Code
SN 29500: Failure Rates for Electronics and Electromechanical Components. Siemens AG Munich, Corporate Technology, Dept. CT TIM IR SI
ISO 13849-1:2015, Safety of machinery -- Safety-related parts of control systems -- Part 1: General principles for design, December 2015
A. Birolini, Reliability Engineering. Theory and Practice, 7th edition, Springer, 2014
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Lienig, J., Bruemmer, H. (2017). Reliability Analysis. In: Fundamentals of Electronic Systems Design. Springer, Cham. https://doi.org/10.1007/978-3-319-55840-0_4
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DOI: https://doi.org/10.1007/978-3-319-55840-0_4
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