在做后端布图的时候，遇到如下问题，
**WARNIMPESI-3025)elay calculation was forced to extrapolate the slew on instance PREICG_X1B_A9G50,Cell type: PREICG_X1B_A9G50,Arc:CK^->ECK^ because it is outside the characterized table range.The actual slew is 0.0063 ns and the lower bound in the table is 0.0126 ns.In some cases,extrapolation can reduce the accuracy of delay calculation.
什么情况下会超出查表范围，是由什么引起的？如果想加强此类问题debug的能力，需要看什么资料，在此先谢谢大家
首次发帖请教大家，希望能得到大家的帮助，谢谢。
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发表于 2020-3-11 13:49:14
IMPESI-3025)
elay calculation was forced to extrapolate the slew on instance PREICG_X1B_A9G50,Cell type: PREICG_X1B_A9G50,Arc:CK^->ECK^ because it is outside the characterized table range.The actual slew is 0.0063 ns and the lower bound in the table is 0.0126 ns.In some cases,extrapolation can reduce the accuracy of delay calculation.
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