Implementation of a Low Dropout Regulator
Amit Patra, Shailendra Baranwal, Ashis Maity, Samiran Dam, Syed Asif Eqbal · 2024
This chapter thoroughly discusses various design trade-offs related to the regulator design. Different biasing philosophies and their merits and demerits are also qualitatively compared. Then a three-stage capacitor-less LDO architecture is chosen as an example where the need for frequency compensation and the choice of different biasing schemes are presented. Finally, an adaptively biased, capacitor-less, low dropout regulator that uses the nested Miller-type frequency compensation is developed. Different design trade-offs like Q −peaking, dynamic response, dynamic range, current efficiency, adaptive-bias ratio, and quiescent current are identified and the close relations among them are presented. Then a detailed design procedure is given to optimize the various trade-offs.