due to heavy switching of the cells. To reduce static IR drop, widen the power network or build a more robust power grid. To reduce dynamic IR drop, lower the toggle rate or add de-cap cells near high-switching cells. KEY Static = steady-state drop (fix with wider grid); dynamic = switching-current drop (fix with de-caps).

Need for Static IR-Drop Analysis Static IR drop is the voltage lost in the power-grid metal before it reaches the VDD pins of the standard cells. Because it lowers the effective VDD seen by the cells, it can introduce timing problems - so it must be analysed and kept within budget. KEY Static IR drop lowers the VDD reaching cells and can break timing, so it must be checked.

Power Trunk A power trunk is the piece of metal that connects an IO pad to the core power ring. KEY A power trunk is the metal connecting an IO pad to the core power ring.

Handling a Chip Hotspot Adding more power straps or widening the existing straps reduces hotspots caused by voltage drop and helps keep the IR drop within about 10%. KEY More or wider power straps reduce voltage-drop hotspots and keep IR drop under ~10%.

Power Gating Power gating is a power-reduction technique that cuts power to a specific region of the chip by shutting it down when it is not in use. KEY Power gating saves power by shutting off supply to idle regions of the chip.