Small-sized and noise-reducing power analyzer design for low-power IoT devices

Power analysis for IoT devices is strongly required to reduce power consumption and realize secure communications, where we need a small-sized power analyzer that can reduce a wide frequency range of noises is needed. In this paper, we propose a small-sized and noise-reduced power analyzer for IoT devices. We utilize a signal averaging method to reduce a wide frequency range of noises. At that time, how to implement a synchronous process between a power analyzer and a target IoT device becomes the key problem. We solve this problem by (a) using synchronization signals generated by a general-purpose I/O interface of a microprocessor and (b) introducing a data-order correction process. We analyze power/energy consumption of the encryption process of LED block cipher on the IoT device and obtain an average power of 146.3mW and energy of 3.84mJ. The proposed power analyzer is just implemented on a 5cm × 5cm board but these results only have 5% errors compared to a high-precision oscilloscope.