Abstract: A system and method for determining the location of a particular device on an integrated circuit chip is described. The system and method utilize apparatus for detecting the emission of light during switching events of devices in the circuit during the circuit's processing of an input calculated to actuate the device whose location is desired. Light emissions from the circuit can be temporally and spatially indexed so as to allow deduction, in combination with the a priori knowledge of the logical operation of the circuit, of the location of the desired element. In another embodiment of the invention, a series of images of the circuit can be accumulated, representing the circuit's response to a series of different input signals, each input signal being designed to result in the switching of the desired element. The series of images can be compared to determine the location of the desired element.

Abstract: A system and method for determining the location of a particular device on an integrated circuit chip is described. The system and method utilize apparatus for detecting the emission of light during switching events of devices in the circuit during the circuit's processing of an input calculated to actuate the device whose location is desired. Light emissions from the circuit can be temporally and spatially indexed so as to allow deduction, in combination with the a priori knowledge of the logical operation of the circuit, of the location of the desired element. In another embodiment of the invention, a series of images of the circuit can be accumulated, representing the circuit's response to a series of different input signals, each input signal being designed to result in the switching of the desired element. The series of images can be compared to determine the location of the desired element.

Abstract: Methods for the ready identification of dynamic defects using switching induced light emission from CMOS gates in complex integrated circuits such as microprocessors are described. The rapid increase in the complexity of logic circuits means that practical gate level identification of the sources of dynamic errors will require methods other than the gate by gate tracing of every possible path taken by a given set of instructions. The methods described here are based on the ability of picosecond imaging circuit analysis to detect the switching activity of every gate of a complex circuit in a single, passive measurement, and the ability of data processing today to compare large two- and three-dimensional files.

Abstract: A system and method for identifying long paths in an integrated circuit are described. An integrated circuit chip is subjected to input test signals of progressively shorter cycle time until the chip fails to produce a correct output. The cycle time of the signal resulting in the failure of the chip is defined as T. A signal having cycle time T'=T+.DELTA.T is then applied to the integrated circuit, where the signal of cycle time T' is known to result in proper operation of the chip. The chip is then observed for switching activity during the period .DELTA.T which occurs beginning at a time T measured from the beginning of the second signal of duration T' until the end of the signal of duration T'. The location of the switching activity is used to identify the path or paths of the circuit that resulted in failure of the chip. In a preferred embodiment of the invention, the switching activity is detected using an optical measurement system capable of detecting light generated by transistor switching activity.