Electromagnetic interference (emi - electromagnetic interference) for a pulse frequency modulation (pfm - pulse frequency modulation) - mode of a switching regulator

摘要

A circuit and a method for providing a switch controller configured to provision of a pulse frequency modulation (pfm – pulse frequency modulation) - operating mode with reduced electromagnetic interference (emi electromagnetic interference), comprising an output stage, which is configured for the provision of a switching, comprising a first and second transistor, a detection circuit, which is configured for the provision of a detecting of the output current information from an output stage and a current limit reference, a first digital - analogous to that of - converter (dac – digital - to - analog converter), which is configured to provide a signal to the current limit reference, an adder function, which is configured to provide a signal to the first digital - analogous to that of - converter (dac – digital - to - analog converter), and a linear feedback shift register (lsfr – linear feedback shift register), which is configured to provide a signal to an adder function, followed by the first digital - analogous to that of - converter (dac – digital - to - analog converter), and the lsfr receives a clock signal from the output stage.