US 6,983,434 B1
Differential via pair impedance adjustment tool
Mark D. Frank, Longmont, Colo. (US); Jerimy C. Nelson, Fort Collins, Colo. (US); and Karl J. Bois, Fort Collins, Colo. (US)
Assigned to Hewlett-Packard Development Company, L.P., Houston, Tex. (US)
Filed on Feb. 13, 2003, as Appl. No. 10/366,489.
Int. Cl. G06F 17/50 (2006.01)
U.S. Cl. 716—5 21 Claims
OG exemplary drawing
 
1. A computer-implemented method for adjusting impedance of a differential via pair in an electrical circuit layout, comprising:
identifying a differential via pair in a circuit design database, said differential via pair having an odd mode characteristic impedance needing adjustment;
establishing a region around said differential via pair in which circuit elements may be modified to adjust said odd mode characteristic impedance of said differential via pair; and
adjusting at least one of said circuit elements in said electrical circuit layout in said region until said odd mode characteristic impedance is closer to a desired odd mode characteristic impedance value.