Patent ID: 7530035

Claim:
An automatic power grid synthesis method for synthesizing power grid in a circuit area, wherein the circuit area has at least one power consuming module and at least one power pin, and the automatic power grid synthesis method includes: selecting at least one representative point in each power consuming module; dividing the circuit area into a plurality of regions in accordance with positions of each representative point and each power pin; calculating overall power grid density of each region in accordance with the positions of each power pin and each power consumption or current requirement at each representative point; and synthesizing the power grid in each region according to overall power grid density of the region, wherein the step of calculating overall power grid density of each region in accordance with the positions of each power pin and each representative point includes: calculating a power grid density between each power pin and each representative point; and calculating overall power grid density between each power pin and each representative point of each region in accordance with the power grid density, wherein the step of calculating the power grid density between each power pin and each representative point includes, for each representative point: calculating a pair of simultaneous equations: I m = ∑ j = 1 n ⁢ I j , and I 1 ⁢ R 1 = I 2 ⁢ R 2 = … = I n ⁢ R n = α ⁢ ⁢ V DD , wherein I m is overall consumption current of the power consuming module, I j is the current through the jth power pin, n is an integer number greater than 0, R n is the resistance between the nth power pin and the representative point, V DD is the voltage of the power pin, and α is the voltage-drop quotiety of the nth power pin to the representative point whereof; selecting one solution set from a plurality of solution sets of the above simultaneous equations to get the resistance between each power pin and the representative point; and calculating the power grid density between each power pin and the representative point according to the resistance between each power pin and the representative point.