The substrate noise detector for noise tolerant mixed-signal IC

A new type of substrate noise detector is proposed. It is embedded in a mixed-signal IC and monitors the level of substrate noise. Voltage comparators are used to detect errors and a counter tracks the number of errors periodically. From the number of errors, the level of substrate noise is estimated using the probabilistic approach. This type of detector is useful in that it monitors substrate noise in real-time. Using this, various adaptive algorithms become feasible to reduce substrate noise. The details of the detector circuits are presented.