Delta-sigma modulator based mixed-signal BIST architecture for SoC

This paper proposes a mixed-signal built-in self-test (BIST) architecture based on a second-order delta-sigma modulator. This modulator, which incorporates design-for-testability (DfT) circuitry, is capable of testing/characterizing itself using digital stimulus. This characteristic is attractive for implementing the modulator as an on-chip analog signal analyzer. When applied for mixed-signal BIST, the modulator-based analog signal analyzer is first characterized using digital stimulus. Then the analyzer is utilized to characterize the stimulus generator in the BIST application. Some critical implementation issues of the BIST architecture are also discussed.