Test of CMOS circuits based on its energy consumption

A modified Keating-Meyer technique to test CMOS circuits by measuring its energy consumption is presented. The circuit is fed by a capacitor being successively recharged while it is excited by a set of test vectors. A Binary Counter is incremented after a quantum of energy has been supplied to the CUT while the circuit is excited by test vectors. The energy cronogram for a given vector set is defined as its Energy Signature. Preliminary experiments show how this energy signature could be used to discriminate non-defective from defective circuits. If the test is applied at a sufficiently low rate the information obtained is equivalent to I/sub DDQ/ testing. Experimental data agree with predicted results and show how bridging and open faults are detected with this method.