US 12,007,440 B1
Systems and methods for scan chain stitching
Puneet Arora, Noida-Uttar Pradesh (IN); Subhasish Mukherjee, Noida-Uttar Pradesh (IN); Sarthak Singhal, Noida-Uttar Pradesh (IN); Christos Papameletis, Apex, NC (US); Brian Foutz, Charlottesville, VA (US); Krishna V Chakravadhanula, Vestal, NY (US); Ankit Bandejia, Greater Noida-Uttar Pradesh (IN); and Norman Card, Vestal, NY (US)
Assigned to Cadence Design Systems, Inc., San Jose, CA (US)
Filed by Cadence Design Systems, Inc., San Jose, CA (US)
Filed on Jun. 23, 2022, as Appl. No. 17/847,421.
Int. Cl. G01R 31/3185 (2006.01); G01R 31/317 (2006.01); G06F 11/267 (2006.01); G06F 30/333 (2020.01); G11C 29/32 (2006.01)
CPC G01R 31/318536 (2013.01) [G01R 31/318547 (2013.01); G01R 31/31704 (2013.01); G01R 31/3185 (2013.01); G01R 31/318558 (2013.01); G01R 31/318563 (2013.01); G01R 31/318583 (2013.01); G06F 11/267 (2013.01); G06F 30/333 (2020.01); G11C 29/32 (2013.01); G11C 2029/3202 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A computer-implemented method for forming scan chains for a test mode among a plurality of test modes of an integrated circuit, comprising:
identifying scan chain elements in a design of the integrated circuit associated with the test mode, wherein the scan chain elements comprise integrated circuit elements that are configured to be connected together into scan chains;
grouping the scan chain elements based on scan chain element grouping criteria into a plurality of scan chain groups;
identifying a number of scan chains for the test mode;
assigning each scan chain to one of the plurality of scan chain groups;
balancing scan chain elements within each of the plurality of scan chain groups among the scan chains assigned to the each scan chain group, wherein balancing includes reducing a difference between numbers of scan chain elements in each scan chain assigned to the each scan chain group; and
connecting scan chain elements to form the number of scan chains for the test mode in response to the scan chain element balancing.