Author : Asha Y N 1
Date of Publication :24th May 2018
Abstract: Engineering Change Order (ECO) is important in correcting the late-found errors that arise commonly in designing sequential circuits. As the number of corners and number of modes increases, the possibility of setup and hold conflict raises. Hold times violations are critical as they lead to permanent failures in the design. A hold time ECO flow is proposed in the paper to fix negative min path violations. It uses buffer insertion and cell replacing as the main techniques to increase the delay of the path so as to make the margin more positive. The proposed methodology increases the time margin by 74.77% .The total negative slack and worst negative slack got improved by 91.68% and 87.01% respectively. It is found that 63.87% hold violated paths can be fixed using the proposed methodology.
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