Power consumption monitoring device for a power source

Examples are disclosed for an integrated circuit (IC) device coupled to a battery-operated power supply unit, such as an IC in a mobile computing device or wireless phone, to accurately determine energy usage drawn from the power supply unit under rapidly dynamic circumstances. A current sense signal of a power line from the power supply unit is digitized. The digitized current sense is added to an accumulator at a rate that is approximately proportional to a voltage of the power line from the power supply unit. The accumulator is then outputted and scaled to units relevant to energy measurements. The energy measurement is used to estimate remaining battery life. Triggering the digitization of the current sense signal may be by use of a pulse generation circuit, or by use of an overflow indicator of an accumulator for a digitized voltage sense signal. Other examples are described and claimed.