A Bipolar Process Based On The "linear Regulator Design

The content of this thesis is to design a Low Dropout linear regulator widely used in portable equipments with property of high accuracy of the output voltage and prolonging the durable time of the batteries. Therefore it’s suitable for the application of portable equipments such as cellular phone, PDA, MP3player, etc.In this thesis, the LDO regulator allows the output voltage changes within a certain range depending on the external resistor. The LDO linear regulator works by the comparison of band-gap reference voltage and the feedback voltage.This signal controls the conduction devices connecting input and output, makes and output voltage stability. The linear regulator’s output voltage is very stable. The input rang is from2V to7V, while the output voltage which is from1.5V to3.3V can be regulated by using different feedback resistors.On the basis of the analysis of the LDO linear regulator architecture, function and principles of the LDO internal circuit structure and the various sub-moduleshave carried out the analysis.At last, the function verification and the electrical characteristics simulation are done by HSPICE based on CSMC01μm36V BJT process. Focused on the temperature characteristics of the reference the error amplifiergain, common mode rejection ratio, PSRR, slew rate overvoltage, overtemperature, overcurrent protection function Simulation results show that, the function of regulator is realized and the characteristics meet the definition requirements, and theoretical analysis is verified.