Desing and self-test for switched-current building blocks

Abstract

This switched-current memory cell with a built-in self-test option serves as a building block for a range of analog functions. As an example application, the authors present a divide-by-two circuit for reference signal generation in algorithmic A/D converters. They also describe two self-test approaches for these building blocks and evaluate their effectiveness. The self-test functions are easy to apply, require very little overhead, and result in fault coverage up to 95% for shorts and 60% for open circuits. Analysis reveals that 100% testability may not be achievable in a cost-effective way for mixed-signal circuits.