STA过程中 SDF-036 warning

haier822

在PT的log文件中产生了如下warning:
Warning: The sum of the setup and hold values in the cell 'inst_top/inst_module/x_buf_reg_6_' for the arc between pins 'CP' and 'D' is negative, which is not allowed. To make it positive, the minimum hold value has been adjusted from -0.403546 to -0.253592.  (SDF-036)
Warning: The sum of the setup and hold values in the cell 'inst_top/inst_module/x_buf_reg_6_' for the arc between pins 'CP' and 'ENN' is negative, which is not allowed. To make it positive, the minimum hold value has been adjusted from -0.810711 to -0.269886.  (SDF-036)
Warning: The sum of the setup and hold values in the cell 'inst_top/inst_module/x_buf_reg_6_' for the arc between pins 'CP' and 'ENN' is negative, which is not allowed. To make it positive, the minimum hold value has been adjusted from -1.204120 to -0.392578.  (SDF-036)
.........

我查了下SDF-036的帮助，

SDF-036 (warning) The sum of the %s values in the cell ’%s’ for
the arc between pins ’%s’ and ’%s’ is negative, which is not
allowed. To make it positive, the %s value has been adjusted
from %f to %f.
DESCRIPTION
This warning message occurs when the sum of the setup and hold values is negative
for a given arc. Note that negative values for either the setup time or hold time
are allowed; however, their sum must always be greater than 0.
WHAT NEXT
This is a warning message only. No action is required because the %s time has been
automatically adjusted to give a positive sum for the setup and hold times.

请教下，这个警告的具体原因是什么，不是太懂。谢谢

icfbicfb

这个没有办法吧，谁要 sdf是这个样子呢，

sdf可以允许负的value， 也可以是0值，

如果不放心的话， 用pt SPEF flow看看吧

haier822

谢谢~

n1991i

回复 2# icfbicfb


   这个对最后signoff有影响吗？

ZHZIC

这个问题怎么解决。。。还是不需要解决

西巴

您好，这个问题需要解决嘛还是不需要呀？要是解决的话该怎么解决呀

xm6webn

是不是不用解决，知道就好？

xm6webn

请教一下楼主，是不是可以不用管这个warning？已经自动帮忙修过了是吗？