Buck Pwm Mode Dc-dc Switching Power Supply Analysis And Design

This thesis discussed a current feedback PWM of step-down DC-DC converter with a built-in internal power MOSFET and synchronous MOSFET. It provides fast transient response and eases loop stabilization. Fault condition protection includes thermal shutdown and over voltage protection. It is very convenient for customers because only a few outside devices are needed when the converter is used.Firstly, the different topology configurations of DC-DC converter were introduced and current-control-mode and voltage-control-mode were compared in the thesis. Advanced Current Mode circuit is specially used to ensure lower power consumption; better transient response and less fluctuate of output voltage. Expatiate and discuss current mode of step-down switch mode converter. All the functional blocks were designed and analyzed, it includes Band gap circuit, Error amplifier, OSC circuit, Shutdown protection etc, and simulate these functional block circuits and give results with Hspice.After some point of layout design is raised, the layout of the thesis is finally finished with CSMC process.By the thesis, I achieved global view of complicated circuit modules design, system function realization and hspice procedure. The thesis records many useful data and design experience, and also gives some suggestions for future optimization design.