Power management

A power management circuit includes an electrical power input for receiving electrical power, a controller, a finite state machine circuit in communication with the controller and a first voltage regulator in communication with the controller and the electrical power input and having a first output connected to a first capacitor for storing electrical power and to first electrical circuitry. The controller is configured to cyclically enable the first voltage regulator to supply current to charge the first capacitor. The finite state machine circuit is configured to interact with the controller to control the duration of a first time period of a cycle over which the first voltage regulator supplies current to charge the first capacitor and to control the duration of a second time period of the cycle over which the first voltage regulator does not supply current to charge the first capacitor and during which electrical current is receivable by said first electrical circuitry from said first capacitor.