  This paper proposes a dynamic capacitance matching (DCM)-based RC current
response algorithm for calculating the current waveform of a signal line
without performing SPICE simulation. Specifically, unlike previous method such
as CCS model, driver linear representation, waveform functional fitting or
equivalent load capacitance, our algorithm does not rely on fixed reduced model
of both standard cell driver and RC load. Instead, our algorithm approaches the
current waveform dynamically by computing current responses of the target
driver for various load scenarios. Besides, we creatively use symbolic
expression to combine the y-parameter of RC network with the pre-characterized
driver library in order to perform capacitance matching by considering
over/under-shoot effect. Our algorithm is experimentally verified on 40nm CMOS
technology and has been partially adopted by latest commercial tool for other
nodes. Experimental results show that our algorithm has excellent resolution
and promising efficiency compared with traditional methods and SPICE golden
result, especially for application in computing delay, power and signal line
electromigration.
