This application note describes methods to measure device power consumption with the Keithley 2280 Series Power Supplies. 

For the battery-powered devices, the power consumption can be represented by the input current because the input voltage is a constant voltage during a load current measurement. If we can measure the load current under different working modes, we will be able to compute power consumption. As a result, we will be able to deduct the device’s battery life in its active modes and its standby mode.