On the ability of oscillation-based test for detecting deviation faults in switched-capacitor ladder filters

This paper proposes the test of high-order switched-capacitor (SC) ladder filters by means of the oscillation-based test (OBT). The OBT implementation requires converting the filter under test into a non-linear oscillator and the study of different oscillation modes in order to evaluate their convenience for testing purposes. The prediction of the oscillation parameters is good for all the oscillation modes proposed, and it is made using a combination of analytical and graphical methods. The fault simulation results show an improvement of the range of deviation-fault detection with the additional oscillation modes. A deeper study allows establishing the modes that are useful for improving the detection of hard-to-test capacitors or for widening the detected deviation range. Additionally, are determined the combination of modes that present the better trade-off between fault detection and test resources.