Energy efficient designs are the need of the hour in this IoT era. IOT based solutions are gradually adopted in real life applications. The majority of the systems that are used IOT are signal processing with a miniaturization to fit into the small enclosure. Efficient VLSI architectures for signal processing are needed here, so the   designer shall need to have an idea of designing a high-performance VLSI circuit that does all the required signal processing activities. The majority of the real-life signal processing does not require accurate processing where one needs to spend more battery power in computing and one can enhance the battery life if he/she can build the design using approximation which will not make any difference in the final output if it is computed by accurate or approximate. Approximate computing will reduce the required power consumption and enhance the speed.