internal power計算

请问要如何计算一个反向器的 internal power
察看了primepower manual是说
Internal energy = rise_energy + fall_energy
那么这两个值应该如何取得?
我打算建立一个cell library

run spice to see the current (Ivss) during the 0->1 + 1->0
P=V*Ivss

how to reduce cell internal power of a circuit using dc_shell

please help me in  to reduce power