Research And Design Of Digital Power Control Chip With Multiple PWM Outputs

Electronic equipment plays an increasingly important role in human life,and switching power supply,as a crucial part of electronic equipment,is also developing in the direction of high frequency,high efficiency and intelligence.The digital control of switching power supply with its advantages in compatibility,scalability,reliability and size performance,it is developing rapidly and constantly replacing the status of analog control.This thesis studies and designs a digital power control chip with multi-channel PWM output,which can provide generalized and high-precision timing control for various isolated topologies,and at the same time provide good steady-state and transient response for the power system.The multi-channel digital PWM module is the core module designed in this thesis.It is mainly composed of a sub-PWM module,a control module,an edge generation module and an internal multiplexer module.The sub-PWM module can realize two outputs.The programmable adjustment of the edge also adds the fault input processing of the overcurrent signal,the synchronization signal processing of multiple modules in parallel,and the adjustment processing of the multi-phase current sharing;the control module provides many register interfaces to configure multiple output parameters,and at the same time Different output modes can be selected,including open-loop mode,normal mode,phase-shift mode and multiple modes,to provide flexible control methods for multiple power stage topologies;the edge generation module and the internal multiplexer module can be configured based on multiple The PWM output and the edge of the blanking signal generate and output a complex PWM square wave.The digital sliding filter designed in this thesis adopts a single-stage CIC decimation filter structure,which reduces the influence of random noise while maintaining a clear step response,and improves the system stability;the digital compensator adopts an improved PID algorithm to provide the system with The programmable compensation adjustment improves the steady-state and transient performance of the loop;the multi-channel digital pulse width modulator module provides the sampling clock for the above two digital modules at the same time to ensure the performance of the system.The digital power control chip designed in this thesis is designed based on 0.18?m CMOS process,and the area of the digital part is 773×1006?m~2,which can realize the control of various isolated DC-DC topologies.The digital-analog hybrid simulation shows that stable multi-channel PWM output is realized in multiple modes,providing high-precision timing control for multiple isolated topology converters,and achieving good steady-state and transient response.