When talking about discrete semiconductors and transistors there is known............
Q - point
The operating point of a device, also known as bias point, quiescent point, or
Q-point, is the point on the output characteristics that shows the DC collector–emitter voltage (Vce) and the collector current (Ic) with no input signal applied. The term is normally used in connection with devices such as transistors.
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Bipolar transistor biasing - Wikipedia, the free encyclopedia
πQ Quality factor [PiQ]
Predicting the failure rate in discrete semiconductor devices
The model shown here predicts the failure rate of low-frequency diodes. This model predicts the failure rate (λp) for
discrete semiconductor devices using the formula :
λp=λb×πT×πS×πC×πQ×πE / 10^6 hr
where :
λb=The basic failure rate
πT=Temperature factor
πS=Electrical stress factor
πC=Contact structure factor
πQ=Quality factor
πE=Environmental factor
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