An integrated circuit formed on a semiconductor chip includes voltage regulators for stepping down an externally-supplied power voltage to produce an internal power voltage, and internal circuits which operate based on the internal power voltage. The voltage regulators are laid in the area of the buffers and protective elements for the input/output signals and power voltages so that the overhead area due to the on-chip provision of the voltage regulators is minimized. The internal power voltage is distributed to the internal circuits through a looped main power line, with an electrode pad for connecting an external capacitor for stabilizing the internal power voltage being provided on it, so that the internal power voltage is stabilized and the power consumption of the integrated circuit is minimized.