Research on the Development of LDO Chip Technology

Abstract. Whether portable electronic devices are powered by rectified AC mains or by batteries, the power supply voltage will vary over a large range during operation. In order to ensure a stable power supply voltage, almost all electronic devices must be powered by a voltage regulator. In order to meet the requirements of precision electronic equipment, a linear regulator should be added to the input end of the power supply to ensure a constant power supply voltage and achieve active noise filtering. LDO can help achieve this function. This article first introduces the basic concepts of low-dropout linear regulators and sorts out the advantages of low-dropout linear regulators. Secondly, the parameters that need to be studied for LDO are sorted out, which are also the direction for breakthroughs in LDO research. The third part introduces some basic structures of LDO, including the design of LDO structure without external capacitors, the design of bandgap reference LDO structure, and the design of high PRSS structure. Finally, the application of LDO is roughly summarized, as well as the trends and challenges of LDO development.