An off-chip sensor circuit for on-line transient current testing

We propose and evaluate an architecture of an integrated transient current off-chip monitor to facilitate implementation of transient current based testing of CMOS VLSI circuits. The monitor measures the transient current idd(t) by sensing the voltage drop at a resistor and provides the charge delivered to the circuit (i.e. the area under the waveform) as the test observable. Designed in 0.18 μm CMOS technology, the sensor measures the transient supply current and provides the waveform area (i.e. the charge delivered to the circuit). The transient current is measured at the circuit supply rail, by sensing the voltage drop at a resistor connected between the IC supply PIN and the voltage source as shown in Figure 1.