Investigations of on-line/off-line tests for sensors

The demand for reliability verification of a system in the operating phase has increased due to the integration of analog and/or digital circuits into more fields of application. It is known that sensor parameter variation in analog circuits leads to faulty results. Determining whether an operation point is to be tolerated needs to be handled in the operation phase. The proposed methods achieve high fault coverage and needs no additional analog test input. It is shown that an online response evaluation is as good as an offline. A temperature measurement system is the example used in this experiment. A comparison is done with other test methods, supply current supervision and the correlation of the output voltage to the supply current.