Study Of A High Performance Low-Dropout Linear Regulator

With the rapid development of electronic information industry, the power technology which isessential for a variety of electronic equipment will become increasingly important. As a newgeneration of integrated circuits, Low dropout linear regulator (LDO) regulator, can provide lownoise and stable voltage for the follow-up circuit. Being with small size, and high supply rejection(PSR), it will consume low power and produce low noise which are advantages comparing withother products. In addition, with good load transient response and linear transient response, theLDO can be widely used in various consumer electronics, automotive electronics and other fields.With the advances in technology and market changes, the performance of the LDO is also need tobe improved. Therefore, the LDO design with excellent performance will become a research focusin power chip set field and has important practical applications and theoretical significance.In order to effectively reduce the influence on the character of the RC oscillator, which is madeby low-frequency noise of power, a high-performance low dropout linear regulator LDO is designedfor high precision RC oscillator, with its input voltage 4.8V, the output voltage 4.5V, and the loadcurrent range of 0.5mA ~ 50mA. The LDO has good temperature characteristics, high power supplynoise rejection capability, it can also work stably under various load conditions. The CSMC CMOS0.5μm simulation process is used and taped out in the whole RC oscillator project.The thesis firstly analyzes the basic structure and working principle of the LDO design,provides with the important performance parameters, and does some research on a few key issues. Itstudies and explores deeply and specifically in the absence of transport put Bandgap referencevoltage source, the basic structure and working principle of the LDO frequency compensation,error amplifier, the LDOs large signal response, and several other parts, including no second-ordercurvature compensation op amp reference, error amplifier, current limit circuit and short circuitprotection. It then does some Circuit analysis and designs for each module within the system, showsthe simulation results, and finalizes the layout of the entire RC chip.