Research And Design Of Buck DC-DC Switching Power Converter With Adaptive Slope Compensation

The development of many fields is fast in all aspects since the beginning of the new century.Among them,technology is particularly prominent with various portable electronic product emerging and rapidly changing.The continuous development of these products has brought huge convenience to people’s lives with higher performance requirements for power management chips.The power chip is the basis of a power supply required to supply other parts for most electronic products.The power chip controlled by current mode has become the mainstream used today due to its fast transient response speed,strong load capacity,and high conversion efficiency.This thesis takes a Buck-type DC-DC converter based on peak current mode control with PWM modulation as the research object.This thesis comprehensively studies the basic theory of Buck power system and the main technology used.The following is an overview of the research content:1.This section described the background of this research.The significance of the research is clarified by comparing the current research status of switching power supply chips at home and abroad in this section.The basic working principle of the Buck switching power supply to be studied this time is introduced in detail.2.The overall architecture of the Buck DC-DC switching power converter designed this time is introduced in this section.Some important modules are specifically analyzed and introduced based on this.In these module,the slope compensation circuit is designed innovatively where a new type of adaptive slope compensation circuit scheme is proposed.Through separate simulation of the circuit,it is verified that each module has good performance and can meet the design requirements of this time.3.The overall structure of the Buck-type DC-DC converter designed is proposed and the selection rules of the system peripheral devices are introduced.On this basis,the 0.5um BCD process is used in Cadence to simulate and verify the important parameters of the system circuit using the Spectre simulation tool.The Buck DC-DC input power supply voltage range is 5.5V-40 V,the internal LDO stable supply voltage is 5V,the output voltage of the system is stable at 4.28 V,the maximum load current is 2A,the ripple voltage is 10 m V,the load regulation rate is 0.8%,and the linear adjustment rate is 0.014%.As can be seen from the above,the Buck converter of this design has good performance and can provide stable power.