A Sub-1V Analog-Assisted Inverter-Based Digital Low-Dropout Regulator with a Fast Response Time at 25mA/100ps and 99.4% Current Efficiency

To mitigate large voltage droop caused by sub-ns dynamic current transitions in system on chips (SoCs), this paper proposes a fully integrated analog-assisted inverter-based digital low dropout regulator (LDO) to obtain a fast response time with 160mV droop at 25mA/100ps featuring 99.4% current efficiency, and 16mV DC load regulation in sub-1V operating range by using a dynamic-step quantizer and a trip-point controller. The proposed quantizer is implemented with an inverter-based flash ADC to achieve high speed without consuming large power while the trip-point controller corrects the DC error of the inverter-based ADC. Besides, the assistant analog LDO is employed to provide fine-grain regulation and remove ripple from the output voltage.