An optimal 4-bit absolute-value detector with low energy consumptions and delays

In electronic engineering, absolute value comparators are key in various applications like finding use in audio, image processing, control systems, and more. This research focuses on optimizing a 4-bit Absolute-Value Detector (AVD) for low energy consumption and minimal delay. The main reason why the 4-bit AVD is focused on is that it exists a strong correlation between four-bit AVD and higher-bit AVD, as they share similar design principles. The circuit mainly comprises an Absolute Value Converter and a Comparator. This research refines traditional logic formulas for the converter, employing CMOS logic for efficiency. In comparator design, topologies are evaluated, selected the one with minimal critical path delay. To balance energy and delay, the Logical Effort theory and "Origin" software are utilized for parameter optimization theoretically and practically. This approach ensures an optimal circuit design for performance and efficiency. In the end of the paper, problems in practical application are also pointed out and the potential solutions are given.