A Temperature Sensing System With Encrypted Readout Using Analog Circuits

Low power integrated compact sensors for applications such as IoT and arrayed biomedical sensors are essential for today's technology. However, security is not incorporated in these sensors and are typically added after implementation using digital hardware or software. In this paper, we demonstrate a temperature to time sensing system with a discrete level encryption process using real-time analog circuitry and minimal processing power. The encryption uses the chaotic Lorenz attractor system. The temperature sensor, implemented in 130 nm technology, consumes 195 nW with 0.5 V power supply. The encryption module is simulated in Simulink and implemented at the board level using discrete components on a printed circuit board. Experimental results show that the envisioned chaotic system is capable of accurately encrypting and decrypting the digital temperature signal.