Research On High-Performance High-Efficiency Power Management Chip For Modern Consumer Electronic Devices

Modern consumer electronic devices have developed to highly complex systems. Correspondingly, power budget and volume and power consumption limitations for such devices become more and more tight, which put higher requirements to power management system. To meet them, it is of great importance to study some key techniques concerning voltage regulation capability, conversion efficiency, respond speed and integrity and to find out the proper solutions in power management IC design.Aiming at developing a high-performance high-efficiency switching converter that suits for applying to modern consumer electronic devices, this thesis investigated and discussed the technologies including robust voltage regulation, light-load efficiency boosting and current sensing and gave the corresponding solutions.In order to achieve the widest range for voltage regulation, four-switches buck-boost converter is adopted to realize both step-up and step-down functions. Unlike the conventional control, a green multi-mode control strategy with three-stage seamless transition is proposed in this work. The novel strategy not only enhanced the system efficiency, but also improved the output ripples and line regulation.For the fact that switching power loss dramatically decreases system efficiency under light load condition, burst mode is introduced to reduce such power consumption. Dual-reference scheme is proposed in switching between PWM mode and burst mode to improve stability of the system.Due to the good dynamic performance, current mode control is adopted in this work, in which current sensing is a key concern. A Gm-C filter-based lossless inductor current sensing technique is proposed to realize accurate on-chip current sensing. Since no extra power consumption is induced during current sensing, the system efficiency is improved by a further step.Based on the proposed solutions above, this thesis accomplished the system and block design of a high-performance high-efficiency switch converter with1.5um BCD process. Tape out is carried out and the test results verify that the modules and system can work properly, and the design target is satisfied. The designed converter can meet the requirements of modern consumer electronic devices...