Equivalent IDDQ tests for systems with regulated power supply

This paper presents an equivalent current sensing technique for the applications of IDDQ tests. This is accomplished by monitoring the operations of existing on-chip voltage regulators, which indirectly provides the IDDQ information. Equivalent IDDQ information is obtained by measuring an internal voltage signal of a regulator. Then, the measured data is shifted out using the IEEE 1149.1 standard. IDDQ based test methods are used to post-process those data for screening defective circuits. Experiments were successfully conducted assuming the TSMC 0.18μm CMOS technology. © 2006 IEEE