Power strap (stripe)
Beginner
A wide power wire that runs across the chip on the top layers, like a highway for electricity.
Novice
A wide supply or ground wire on one of the chip’s upper wiring layers, repeated at a regular spacing. Straps on neighboring layers run at right angles to each other and are joined where they cross, forming a mesh.
Expert
Described by layer, width, pitch (the repeat distance), offset and the spacing between the VDD and VSS straps in each pitch. Wider or closer straps lower resistance and wear-out risk but take routing tracks from signals, so the pitch is often varied by region.
Explained in Power planning (Design Flow).
See also: Standard-cell power rail (followpin), Power ring.