The analog built-in self-test (BIST) scheme using a single-bit second-order Σ-Δ modulator as the analog response extractor (ARE) has been proven to be a low-cost solution. For applications where higher resolution or wider bandwidth is required, a higher-order Σ-Δ modulator may be more suitable, since it allows a reduced oversampling ratio (OSR) for a given resolution. The ARE candidates also need to operate at a reasonable range of OSR and tolerate circuit imperfection to serve different test requirements. Two single-loop and two cascaded single-bit fifth-order Σ-Δ modulators are compared. They are digitally testable with the proposed low-cost design-for-testability circuit. The high-order Σ-Δ modulator, a cascade of the second-order and first-order ones, is considered as the best choice for OSR ≥ 16 because of its small hardware overhead, lower sensitivity to the circuit imperfections, unconditional stability, and high flexibility in adjusting to a wide range of OSR. This is verified by simulation results.
|Number of pages||13|
|Journal||Journal of the Chinese Institute of Electrical Engineering, Transactions of the Chinese Institute of Engineers, Series E/Chung KuoTien Chi Kung Chieng Hsueh K'an|
|State||Published - 1 May 2004|
- Analog Response Extractor
- High-order Sigma-Delta Modulator
- Mixed-signal BIST
- Mixed-signal DFT