Inversed Temperature Dependence aware clock skew scheduling for sequential circuits

We present an Inversed Temperature Dependence (ITD) aware clock skew scheduling framework. Specifically, we demonstrate how our framework can assist dual-Vth assignment in preventing timing violations arising due to ITD effect. We formulate the ITD aware synthesis problem and prove that it is NP-Hard. Then, we propose an algorithm for synergistic temperature aware clock skew scheduling and dual-Vth assignment. Experiments on ISCAS89 benchmarks reveal that several circuits synthesized by the traditional high-temperature corner based flow with a commercial tool exhibit timing violations in the low temperature range while all circuits generated using our methodology for the same timing constraints have guaranteed timing.

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