Min-time / race margins in digital circuits
AssigneeTelefonaktiebolaget L M Ericsson (publ)
InventorHans Lindkvist
Life of this patent
Estimating the term…
Abstract
A preferred timing change is automatically selected from a set of candidate timing changes that can be made to address a short path violation in a circuit design. This involves determining an associated cost metric for each of the candidate timing changes, and identifying a lowest cost metric from the associated cost metrics. The candidate timing change associated with the lowest cost metric is selected from the set of candidate timing changes, for use as the preferred timing change. The associated cost metric may represent a cost per resolved source or destination register. Candidate timing changes may variously involve any of a number of techniques for introducing additional delays into a short path of the circuit.
Claims58
A method of automatically selecting a preferred timing change from a set of candidate timing changes that can be made to address a timing problem in a circuit design, the method comprising:
- determining an associated cost metric for each of the candidate timing changes;
- identifying a lowest cost metric from the associated cost metrics;
- and
- selecting for use as the preferred timing change, from the set of candidate timing changes, the candidate timing change associated with the lowest cost metric.
A method of automatically selecting a set of preferred timing changes from a set of candidate timing changes that can be made to address a set of timing problems in a circuit design, the method comprising:
- for each of the timing problems, determining an associated cost metric for each of the candidate timing changes;
- identifying a least expensive set of candidate timing changes that address the entire set of timing problems and whose combined cost metrics are a lowest combined cost metric;
- selecting for use as the set of preferred timing changes, from the set of candidate timing changes, the least expensive set of candidate timing changes.
An apparatus that automatically selects a preferred timing change from a set of candidate timing changes that can be made to address a timing problem in a circuit design, the apparatus comprising:
- logic that determines an associated cost metric for each of the candidate timing changes;
- logic that identifies a lowest cost metric from the associated cost metrics;
- and
- logic that selects for use as the preferred timing change, from the set of candidate timing changes, the candidate timing change associated with the lowest cost metric.
An apparatus that automatically selects a set of preferred timing changes from a set of candidate timing changes that can be made to address a set of timing problems in a circuit design, the apparatus comprising:
- logic that determines, for each of the timing problems, an associated cost metric for each of the candidate timing changes;
- logic that identifies a least expensive set of candidate timing changes that address the entire set of timing problems and whose combined cost metrics are a lowest combined cost metric;
- and
- logic that selects for use as the set of preferred timing changes, from the set of candidate timing changes, the least expensive set of candidate timing changes.
Dependencies are inferred from the claim text.