Methods and Apparatus for Determining a Switching History Time Constant in an Integrated Circuit Device

• Main Authors: KETCHEN MARK B, PEARSON DALE J, BHUSHAN MANJUL
• Format: Patent
• Language: English
• Published: 29.10.2009
• Subjects: MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

Techniques for inline measurement of a switching history time constant in an integrated circuit device are provided. A series of pulses is launched into a first stage of a delay chain comprising a plurality of delay stages connected in series and having a length greater than a decay length of at least an initial one of the series of pulses, such that the at least initial one of the series of pulses does not appear at a second stage of the delay chain. An amount of time between the launching of the initial one of the series of pulses and the appearance of at least one of the series of pulses at the second stage of the delay chain is determined. The switching history time constant is calculated as a function of a number of stages traversed by the at least one pulse, the determined amount of time, and the decay length of the at least initial one of the series of pulses based at least in part on a switching history of the integrated circuit device.