Research And Implementation On A New Single Inductor Multiple Outputs BOOST Type DC-DC Converter

With the rapid development of electronic products,the internal circuit becomes more complex,more and more integrated unit modules.Single inductor multiple outputs DC-DC converter with only one inductor can achieve multiple output voltage,can significantly reduce the product size,reduce costs,so its research is of great significance.In this paper,a new single inductor multiple outputs BOOST type DC-DC converter is designed.In order to overcome the cross-interference between different output voltages,the traditional single inductor multiple outputs DC-DC converter is mostly used TM timing control,DCM work mode,and this paper uses a new OPDC timing control,adaptive PCCM mode of technical solution,not only can effectively inhibit the cross-interference,with a greater load capacity,but also has a flexible dynamic power output range.In this paper,the topological structure,working mode and cross-interference problem of single inductor multiple outputs DC-DC converter are studied in detail.On this basis,the working principle and advantages of adaptive PCCM mode and OPDC timing control are expounded,and the power level of PCCM mode converter is small signal modeling and analysis.Then,a PCCM mode single inductance three-output DC-DC converter was designed with four dynamic adjustment functions,and the related circuit module is designed.In the design process,a number of measures have been taken to suppress the cross-interference problem.Finally,the whole system has been simulated and verified.This design is based on CSMC0.25?m BCD technology library,the system switching frequency is 1MHz,the input voltage range is 2.2V ~ 3.2V,the three output voltage design is:3.3V,4V,5V,conversion efficiency is higher than 80%.The simulation results show that the system can output three stable operating voltages within a large load range,and the cross-interference problem is also effectively controlled,which fully meets the design requirements.