Measuring System for Microelectric Power

In this paper, we are mostly concerned with the measurement of electric micropower and energy. This parameter is essential to evaluate the energy efficiency of low power devices, such as wireless operated monitoring and control systems. It is also important to measure the standby power consumed by appliances and equipment while switched off. The measurement of power generated by the harvesting systems is another field of application. Thus, it is important to implement the power meters to accurately measure power . The common commercially available wattmeters are inaccurate for these low-power measurements for two main reasons: a limitation on the instrument dynamic range and the intermittent operating mode of some devices. Particularly critical is the current measurement, for the high gains required in most applications. In this paper, a measuring system for microelectric power and energy is proposed. It operates for voltage up to 3 Vpp and current from 1 pA to 5 mA, corresponding to an electric power down to around a fraction of microwatt. In the following, the system architecture is described, also discussing some experimental results obtained during the characterization test.