Patent ID: 7877715
Filing Date: 2011-01-25
Classification: G01R

Abstract:
1. A method to evaluate whether one or more test patterns is power safe for use during manufacturing testing of an integrated circuit that includes a nonuniform power grid and that includes a scan chain with first scan elements associated with a first region of the power grid and with second scan elements associated with a second region of the power grid, the method comprising: obtaining a first threshold that includes a first threshold number of toggles per scan shift cycle for the first scan elements associated with the first power grid region; determining, using a computer, whether a number of toggles by the first scan elements meets the first threshold number of toggles during at least one scan-shift cycle in the course of scan-in of a test pattern within the scan chain; obtaining a second threshold that includes a threshold number of toggles per scan shift cycle for the second scan elements associated with the second power grid region; and determining, using a computer, whether a number of toggles by the second scan elements meets the second threshold number of toggles during at least one scan-shift cycle in the course of scan-in of the test pattern within the scan chain.