An electronic device may include a main circuit including multiple sub-circuits powered by a direct-current (DC) power supply circuit. The main circuit has a main circuit current demand being a time-varying demand for a DC voltage-regulated supply current being a function of a number of the sub-circuits being active. The DC power supply circuit may include multiple DC voltage regulators to provide the main circuit with the supply current and a command decoding and power management circuit to control enablement of the voltage regulators. The command decoding and power management circuit may be configured to detect an instant value of the main circuit current demand and to selectively enable one or more of the voltage regulators based on the detected instant value.