Design Of A Current Mode Boost DC-DC Regulator Based On BCD Process

Based on the project of institute of electronic CAD, Xidian university"Design and research of sub-micro power management integrated circuit", the paper proposes a boost DC-DC converter XD8711 for portable electronic products.Beginnig with studying status and development prospect of SMPS (switching mode power supply), the paper analyzes the principle and the scheme of several DC-DC converters. According to the function and performance, it describes the processes and the operation mode. And then we propose the system scheme and introduce the principle of whole chip. In the chapter of circuit design, the paper analyzes the principle of the main block and designs a digital soft start circuit which can be easily integrated. To assure the system stability and safety, several protection circuits are included.In the basis of the design of system and sub-circuit, the circuit uses the 0.6μm BCD process and simulated by the cadence. The simulation results show that the output voltage can be high to 13V over an input range of 2.5V～5.5V, the efficiency could be 87%. The circuit also has simple architecture, high accurate output and low power loss.