The invention discloses a method for estimating the decoupling capacitors on a
chip of an ASIC based on a chain circuit, and belongs to the field of
estimation of the decoupling capacitors in inhibition of mains
voltage fluctuation. The method comprises: firstly, adopting Star-RCXT to extract parasitic parameters of the ASIC after wiring, and using
Perl to analyze the SPF
file format and included information for the modeling of the chain circuit; secondly, using an Euler formula to realize the equivalence of the capacitors, and compressing the circuit by a Y-
delta conversion method; thirdly, solving the
voltage and the current of various nodes of a compressor circuit, and restoring the solving of the chain circuit; and fourthly, adopting integral idea to obtain the number of decoupling capacitors required to be added according to the principle that the
voltage fluctuation of the nodes cannot exceed 10 percent of the mains voltage. The method estimates the number of the decoupling capacitors on a
chip required to be added between power ground wires, makes the amplitude of mains fluctuation not exceed 10 percent of the mains voltage, and effectively solves the problem of
voltage drop of a power network.