Research on Circuit Architecture of SAR ADC

In the information age, a large number of signals are processed digitally through digital signals, but the physical quantities in the real world are almost continuous. Therefore, when continuous physical quantities are converted into electrical signals through sensors, the obtained signals are continuous electrical signals (analog signals), and a conversion device is needed to convert the electrical signals into digital signals that can be processed. This device is the analog-to-digital converter (ADC), which is known as the bridge connecting the physical world and the digital world. For ADCs, the conversion rate and conversion accuracy are two main indicators. At the same time, it is extremely difficult to design an ADC with both high conversion rate and high accuracy, and there is still a big gap between China and foreign countries in the design of ultra-high-performance ADCs. With the rapid development of China's electronic industry in recent years, the demand for high-precision and high-speed ADCs in electronic design is increasing. Therefore, the design of high-performance ADCs has always been the focus of domestic research. At the same time, with the increasing attention paid to the semiconductor industry in China in recent years, domestic scholars and research institutions have done a lot of research and experiments on improving the performance by adopting different architectures of ADCs. The mainstream ADC architectures include pipeline ADC, SAR ADC, Delta Sigma ADC, etc. Different structures have different advantages in terms of power consumption, conversion rate, and conversion accuracy. Next, a brief introduction to these ADCs will be given.