Various methods and apparatuses are described in which an integrated circuit is organized into rows and columns of macro cells having a layout architecture that includes at least two metal layers and a plurality of traces carrying three or more different potentials of voltage routed by the metal layers. A first, a second, and a third adjacent metal layers extend across the integrated circuit. The plurality of traces carry three or more different potentials of voltage and are routed in the metal layers. A first power trace supplies a VDD voltage potential. A second power trace supplies a VSS voltage potential. A third power trace supplies a third voltage potential to support sleep modes and retain data during sleep modes. All three power supply traces connect to one or more transistors in a first macro cell.