Additional Resources > Windchill Risk and Reliability Practitioner’s Guide > Reliability Prediction Methods > Hybrid Microelectronic Devices > Number of Interconnections
Number of Interconnections
The following points must be observed when counting the number of interconnections (N i.) to be used in the model:
• Each active (current-carrying) wire and each beam lead or solder blob should be counted as one interconnection.
• Redundant interconnections should be counted as only one interconnection.
• A bond should be considered bimetallic if any one of the bond interfaces involves more than one type of metal.
• Active die attach bonds (die to substrate bonds) should not be counted as interconnections.
• If an accurate count of interconnections cannot be obtained, the approximations in Table 3-3 may be made:
Table 3-3. Approximations for Number of Interconnections
Component
Number of Interconnections
Each IC chip bonding pad
1
Each transistor
2
Each diode
1
Each capacitor
2
Each external lead
1
Each chip resistor
2