The Analysis And Research Of A Buck DC/DC Control IC With Large Load Capacity

With the rapid development of microelectronics technology, a variety of electronic devices are springing up like mushrooms, and the power electronic devices as an important part for electronic devices directly determines the performance of the electronic system.As the mobile intelligent terminals developingmore light,more powerful,smaller and thinner, switching power management chip will follow this trend toward low-voltage, high load capacity closely. In recent years,electronic equipmentsis more strict for load capacity.This paper design a DC-DCswitching power management chip with wide range of input voltage and hign load current, with a integrated on-chip powertransistor. the load capacity of this chip is 3A, the range of input voltage is 5.5-36 V and the output voltage is 5V,the fixed switching frequency is 500 KHz.Firstly,this paper introduces current situation of switching power supply and significance of theme studying, analyzes the basic theory of DC-DC switching power supply. Secondly,based on the chip, this paper Focus on how to improve the load capacity of the system. we make a theoretical analysis about the causes and processes.Then givingan appropriate solution based on this Foundation. Finally, through specific circuit,we put the idea into practice. At the same time, Improvingpower efficiency of the chip has done a lot of design considerations: Providing bias to system with the output voltage; the topology uses boost capacitor so that the switching transistor operates in the saturation region.The chip uses a peak current PWM control structure, using piecewise linear slope compensation and integrated anti-slope compensation circuit to maximize load current.Simulation for the design specifications including whether piecewise linear slope compensation modulethat anti-slope compensation circuit is integratedcan improve the load capacity based on the bipolar process of CSMC 2μm 36 V.As a comparison,This paper presents piecewiselinearslopecompensation circuit modulewhich a anti-slope compensation is not integrated, consistent with other modules, the simulations demonstrate the indicators including load capacity meet design requirements.