| abstract |
A low power circuit and method for detects in-situ failures or precursors to failures in solder-joint networks on actual operational devices and packages in the field. An amplifying detector such as provided by a common-gate transistor sources current to the network to generate a signal voltage and a reference voltage that is sensitive to the low voltage applied to the other side of the network. Generation of this self-adjusting reference voltage makes the detection circuit insensitive to the network low-voltage. Additional power savings and performance gains can be provided with the addition of a differential amplifier to set a fixed bias point and a level shifter to cancel noise. The detected failure or precursor of a selected monitor solder-joint network(s) is an indicator of the integrity of other operational solder-joint networks in the package, on the PWB or between PWBs. |