A dynamic output power management unit for a heating circuit (100) of an electronic smoking device is disclosed, the heating circuit (100) having a heating element (10) connected to a power source (20) via a first switching element (30), the unit having at least one voltage detection device to detect voltage values at various points of the heating circuit (100); and a controller (2) configured to deriving a resistance of the heating element (10), estimating a discharge time or a power consumption value of the power source (20) such that an energy converted in a period of time is substantially identical to a predetermined energy conversion value for a same period of time.