Agilent Technologies, Inc.

Peter Maxwell

Jeff Rearick

Peter Mark O'Neill

Victor Johansen

The present invention, in general, provides for a testing system and method for detecting defects within a circuit. A current signature of the quiescent current of the circuit is determined, and certain constant values are calculated based on the current signature using a linear iterative regression. A defect free state for the circuit associated with a minimum quiescent current (I ) is then determined. The I of the circuit for this state is measured, and a signal indicating the I at this state is used along with the aforementioned constant values to create upper and lower threshold values. Thereafter, signals indicating the value of I for a plurality of other states are compared to the upper and lower threshold values. The circuit is determined to be defective if the values of any of the signals is greater than the upper threshold value or is less than the lower threshold value.

System and method for detecting defects within an electrical circuit by analyzing quiescent current

A method for operating a data processing system to provide an estimate of the leakage current expected from an integrated circuit having a known test vector applied thereto. The method generates a graph having a first node connected to a terminal maintained at a first power supply potential and a second node connected to a terminal maintained at a second power supply potential, the first and second power supply potentials having a potential difference of V,. Each edge represents a source-drain connected transistor connected between two nodes as a switch having a resistance that depends on whether the transistor is &ldquo;on&rdquo; or &ldquo;off&rdquo; when the test signals are present. Each node in the graph is assigned a value of 0 or 1, together with the strength of that value. The assignment process also verifies that the circuit is in a valid static state. A leakage current estimate is generated for each path connecting the first and second nodes, and estimates are combined to arrive at the estimate for the integrated circuit. In one embodiment, the leakage current is calculated using an equation having eight components. Four of these represent the leakage current arising from N-type transistors in the circuit and the other four represent the leakage current arising from P-type transistors in the circuit.

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Sunnyvale, CA, United States of America

Peter Maxwell