rise time and fall time of input pulse for simulation

[itsnaushad]

Hi all! could you please tell me what should be the rise time and fall time of input pulse for measuring dynamic power of digital circuits. i have observed that power dissipation depends upon the rise time and fall time of input signal in hspice simulation.

 

[ankitgarg0312]

it depends on rise time and fall time of your input source (real time signal gaenerator)
for simulation purpose we normally assume rise/fall time are 5-10% of clock pulse width.