Physically Unclonable Function Using Ring Oscillator Collapse in 0.5 V Near-Threshold Voltage for Low-Power Internet of Things

Many Internet of Things (IoT) devices have special and demanding design requirements, including limited energy, size, storage and processing capabilities. In addition, many IoT devices may be deployed in public places, making them vulnerable to physical attacks and replication attacks. Therefore, IoT devices are required to provide a solid security against duplication and counterfeiting even with these restrictions. To solve this problem, we propose a low-power physical unclonable function (PUF) for IoTs. The proposed low-power PUF at 0.5 V supply voltage (in near-threshold voltage region) achieves an energy efficiency of 36.7 pJ/b by lowering the bias voltage extremely and operates stably from -20°C to 60°C. In this paper, PUF for low-power IoTs is implemented in a 28-nm CMOS process and occupies 10801μm
²
area.