To figure out this problem, I've designed another simple DFF module.
The detailed information is as follows.
However, I still cannot find where this problem came from and how to fix this.
Please help me out.
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ramp 0.00 at pin 'D' of cell 'ff_reg_reg[1]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'CLK' of cell 'ff_reg_reg[1]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'RSTB' of cell 'ff_reg_reg[1]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'D' of cell 'ff_reg_reg[0]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'CLK' of cell 'ff_reg_reg[0]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'RSTB' of cell 'ff_reg_reg[0]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
Warning: There are 6 out_of_range ramps.
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