International Business Machines Corporation

Scott Henry Mack

Robert Lowell Kanzelman

Brian C Wilson

Sean T Evans

Thomas A Haselhorst

Lance Gordon Thompson

Mark A Williams

Victor A Acuña

Kenneth Michael Caron

Embodiments herein describe performing an engineering change order (ECO) after a physical design team has begun (or finished) a physical design (PD) netlist. However, the ECO may describe changes or additions to the logic and/or nets using component names found in a design netlist that is different than the PD netlist. Embodiments herein rely on generating an equivalents nets file that the maps the components in the design netlist to the components in the PD netlist. When performing an ECO, the PD team can use this file to map the components in the ECO (which are based on the design netlist) to all the equivalent components in the PD netlist. The PD team then selects one of the equivalent components to alter as indicated in the ECO.

Preparing engineering change orders for physical design using boolean equivalence checking tools

In a first aspect, a first method of designing a circuit is provided. The first method includes the steps of (1) providing a model of an original circuit design including a latch; (2) providing a model of a modified version of the original circuit design, wherein the modified version of the original circuit design includes a set of latches associated with the latch of the original circuit design and voting logic having inputs coupled to respective outputs of latches in the latch set; and (3) during Boolean equivalency checking (BEC), injecting an error on at most a largest minority of the inputs of the voting logic to test the voting logic function.

Methods and apparatus for boolean equivalency checking in the presence of voting logic

Methods and apparatus for Boolean equivalency checking in the presence of voting logic

A method, apparatus, system, and signal-bearing medium that in an embodiment apply a latch behavior to a first and second netlist, where the latch behavior exhibits transparent behavior. Flush enabling conditions are applied to the first netlist and a second netlist. For each latch in a first scan chain in the first netlist, a corresponding latch in the second netlist is found. Cones of logic are then extracted from the latches under the constraints enabling the flush operation, and the cones of logic are compared for functional equivalence. If all the cones are functionally equivalent, then the flush reset states of the netlists are functionally equivalent. If at least one of the cones is not functionally equivalent, then the flush reset states of the two netlists are not equivalent.

Equivalence checking of scan path flush operations

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Rochester, MN, United States of America

Scott Henry Mack