Testing mixed signal ASICs through the use of supply current monitoring

The authors investigate testing of mixed signal integrated circuits. Several approaches are proposed, most requiring careful partitioning of the analogue and digital sections. However, the use of supply current monitoring is applicable to both digital and analogue sections. Digital testing has been widely investigated, concentrating on quiescent I_ddq testing. Using pseudo-random binary test signals with supply current testing, high fault coverage of both catastrophic FET faults and gate oxide shorts in the analogue section is shown to be obtainable. Use of on-chip supply sensors has also been investigated