Reducing Ground-Bounce Noise and Stabilizing the Data-Retention Voltage of Power-Gating Structures

Power gating is one of the most effective techniques in reducing leakage power, which increases exponentially with device scaling. However, large ground bounces during abrupt changes of power mode may cause unwanted transitions in neighboring circuits, which should still be operating normally. We analyzed this ground-bounce noise and reduced it with novel power-gating structures that utilize holistic integrated device-circuit-architecture approaches. We control the amount of charge in the intermediate nodes of the circuit that passes through the sleep transistors during the wake-up transition and stabilize the minimum virtual power supply voltage required for data retention. These techniques have been proven in silicon using 65-nm bulk CMOS technology.