A wakeup rush current and charge-up time analysis method for programmable power-gating designs

Programmable power-gating structure is often implemented in advance low-power designs where switch cells are connected into a number of separate daisy chains which can be configured into a trickle charge chain and a main chain. The main chain can also be programmed with desired turn-on time to achieve short charge-up time while meeting max rush current constraints during wakeup. A chain latency annotation method is presented in this paper to model the chain configurations and programmable main-chain turn-on time of complex power-gating designs in the wakeup rush current and charge-up time analysis.