Hybrid Digital Linear Switched Capacitor Voltage Regulator

Abstract

An on-die voltage regulator is provided that can provide much higher conversion efficiency than traditional solutions (e.g., FIVR, LDO) during standby mode of a system-on-chip (SOC), significantly reducing power consumption during connected standby mode. The VR operates as a switched-capacitor VR under low load current conditions typical during SOC standby mode, while automatically switching to digital linear VR operation to handle sudden high load current conditions upon exiting standby. Using a digital proportional-integral-derivative (PID) controller or a digital proportional-derivative-average (PDA) controller, very low-power operation is achieved, along with stability and robustness. Therefore, the hybrid VR achieves much higher conversion efficiency than a linear voltage regulator (LVR) for low load current conditions (e.g., less than 500 mA).