Design and Implementation of Trim-free Voltage and Current References for Energy-Efficient IoT Applications

Abstract

The Internet of Things (IoT) has witnessed exponential growth, enabling a plethora of smart applications ranging from wearable devices to smart cities. However, the widespread adoption of IoT devices hinges on their ability to operate with minimal power consumption. However, one of the critical challenges in IoT design is the need for ultra-low power consumption to enable long battery life and energy harvesting. Moreover, systems powered by energy harvesting sources need to operate effectively with lower supply voltages. Similarly, systems relying on miniaturized batteries must be capable of functioning over a broad range of supply voltages, eliminating the necessity for voltage regulators. Low power, high precision and low supply voltages are the primary requirement of an IoT based design. Voltage and current references are the basic blocks used in IoT based system. This thesis focuses on the designing of Voltage and current references circuit with low power consumption, low supply voltage and high precesion without using any external calibration circuit. Firstly. the thesis introduces a All-in-one low-power, voltage and current reference design into a single block without using any external calibration. The design works with a supply of 1V with a power consumption of 37nW shows temeprature invariancy through a wide tempertaure range of -40 to 100°C. This design specification shows the best results among the previous state-of-art works. Furthermore, in response to the growing demand of low power high precsion circuits we designed an ultra-low power current reference circuit which is independent of temperature, voltage and process without using any extra trimming circuitry. The design works with a supply of 0.8V and generates a refrence current of 543pA by consuming a power of 3.3nW. Lastly, we come up with a novel design of voltage reference. The proposed work is designed in 180nm with a supply voltage of 0.6V with an excellent Line sensitivity of 0.0012/V without using an external calibration circuit. In summary, this thesis encompases the circuit designing of low power, low voltgae and high accuracy voltage and current references without using resistors, amplifiers and external calibration circuit used in IoT applications.