An electronic device comprises one or more functional units, each functional unit being clocked by a respective clock signal. The electronic device further comprises a monitoring unit for providing a real-time estimate of an electrical current consumed by the functional units. The monitoring unit provides the real-time estimate on the basis of characteristic signals. The characteristic signals may comprise one or more of said clock signals, or one or more clock generating signals used to generate said clock signals. The electronic device may further comprise a power regulator responsive to the real-time estimate. A method of estimating in real-time an electrical current consumed by one or more functional units is also described.