Circuit reliability

Circuit reliability (also time availability) (CiR) is the percentage of time an electronic circuit was available for use in a specified period of scheduled availability. Circuit reliability is given by where T _o is the circuit total outage time, T_s is the circuit total scheduled time, and T _a is the circuit total available time. ${\displaystyle T_{s}=T_{a}+T_{o}}$

In addition, circuit reliability is the expected lifespan of operation of a functioning system under nominal conditions.

 This article incorporates public domain material from the General Services Administration document "Federal Standard 1037C" (in support of MIL-STD-188).

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