Design And Implementation Of A Single Inductor Quadruple Output DC-DC Converter With High Light Load Efficiency

In recent years, single-inductor multiple-output DC-DC converter has been a research focus in the field of power management because of less off-chip inductors, greatly reducing the circuit size and cost. The SoC system integrates a number of functional modules, each module requires a separate power supply, which determines the use of single-inductor multiple-output DC-DC converter for the SoC power becomes a research trend. However, there are still many difficulties during the research of single-inductor multiple-output DC-DC converter, such as limited output load range and low energy conversion efficiency at light load.Therefore, the study of a wide load range and high light-load efficiency of single-inductor multiple-output switching power converter has important theoretical significance and practical value.In this thesis, a novel adaptive PWM/PSM switching mode control Single Inductor Quadruple Output converter is designed, enabling wide output load range in four outputs, and a high energy conversion efficiency can be maintained in the whole load range.This thesis firstly analyzed the various losses of the converter, including switching loss and conduction loss, and in-depth study of the relationship between the various loss varies with the load current, and the optimum load switching point in PWM/PSM switching mode. Depending on the four load current, the converter load is divided into three load conditions, the total load is light load, each way are heavy load and the total load is heavy and where a road or a few roads load are light load. Also, the control mode under different load conditions is researched and determined, thereby ensuring high energy conversion efficiency under various load conditions. In order to achieve adaptive mode switching mode, the thesis has proposed zero-crossing detection circuit and a secondary duty cycle detection circuit, while the mode switching circuit to automatically adjust working modes.In this thesis, based on Chart 0.35?m CMOS process, the circuit and layout design of adaptive PWM/PSM mode switching SIQO converter process is completed. The Post-Simulation results show that: SIQO converter enables four-way wide load range from OmA to 250mA, with 91% peak efficiency under heavy load and more than 85% efficiency at light loads. In PWM mode, the output voltage ripples are less than 10mV and ripples are less than 30mV at PWM/PSM switching mode. All the results basically meet the requirements.