An integrated circuit (51) comprises a power distribution network having a power pad (53) and a ground pad (55) arranged at diagonally opposite corners of the integrated circuit (51). A power bus (67, 69) and a ground bus (71, 73) supply power to circuit elements on the integrated circuit, for example standard cells (61a, 61b) or standard sub-blocks (63). A plurality of decoupling cells (65) are provided on the power distribution network for maintaining a static current flow between the power pad (53) and the ground pad (55). The power bus and ground bus are configured such that the combined length of the power bus and the ground bus is made the same for all circuit elements on the integrated circuit, thereby reducing on chip voltage variation.