Operational mode changes in a system-on-a-chip (SoC) integrated circuit in a complex device such as a mobile phone cause spikes in current demand which can cause voltage droops that disrupt operation of the SoC. A hybrid parallel power supply capacitively couples a switching-mode power supply and a low-dropout voltage regulator in parallel to provide high efficiency and fast response times. The low-dropout voltage regulator may include a class-AB operational transconductance amplifier driving the coupling capacitor. The switching-mode power supply and the low-dropout voltage regulator can regulate their outputs to slightly difference voltage levels. This can allow the switching-mode power supply to supply most of the SoC's current demands.