Systems and methods for reducing electromagnetic interference using switching frequency jittering

A system for regulating a power converter, the system comprising:

• a signal processing component configured to:
• receive a first input signal and a second input signal;
• process information associated with the first input signal and the second input signal;
• and
• output a drive signal to a switch based on at least information associated with the first input signal and the second input signal, the drive signal being associated with a switching frequency related to a power converter including the switch;
• wherein:
• the first input signal is associated with at least a feedback signal related to an output voltage of the power converter;
• and
• the second input signal is associated with at least a primary current flowing through a primary winding of the power converter;
• wherein the signal processing component is further configured to:
• change a peak value of the primary current within a first predetermined range;
• and
• change the switching frequency of the power converter within a second predetermined range;
• wherein the signal processing component is further configured to randomly change the peak value of the primary current within the first predetermined range.

A system for regulating a power converter, the system comprising:

• a signal processing component configured to:
• receive a first input signal and a second input signal;
• process information associated with the first input signal and the second input signal;
• and
• output a drive signal to a switch based on at least information associated with the first input signal and the second input signal, the drive signal being associated with a switching frequency related to a power converter including the switch;
• wherein:
• the first input signal is associated with at least a feedback signal related to an output voltage of the power converter;
• and
• the second input signal is associated with at least a primary current flowing through a primary winding of the power converter;
• wherein the signal processing component is further configured to:
• change a peak value of the primary current within a first predetermined range;
• and
• change the switching frequency of the power converter within a second predetermined range;
• wherein the signal processing component is further configured to randomly change the switching frequency of the power converter within a second predetermined range.

A system for regulating a power converter, the system comprising:

• a comparator configured to receive a first input signal and a second input signal and generate a comparison signal based on at least information associated with the first input signal and the second input signal, the first input signal being associated with at least a feedback signal related to an output voltage of a power converter, the second input signal including a third input signal and being associated with at least a primary current flowing through a primary winding of the power converter;
• and
• a driving component configured to receive the comparison signal and output a drive signal to a switch based on at least information associated with the comparison signal, the drive signal being associated with a switching frequency related to the power converter including the switch;
• wherein the comparator and the driving component are configured to, in response to at least the third input signal, change a peak value of the primary current within a first predetermined range and change the switching frequency of the power converter within a second predetermined range;
• wherein the third input signal is related to a current-jittering signal.

A system for regulating a power converter, the system comprising:

• a comparator configured to receive a first input signal and a second input signal and generate a comparison signal based on at least information associated with the first input signal and the second input signal, the first input signal including a third input signal and being associated with at least a feedback signal related to an output voltage of a power converter, the second input signal being associated with at least a primary current flowing through a primary winding of the power converter;
• and
• a driving component configured to receive the comparison signal and output a drive signal to a switch based on at least information associated with the comparison signal, the drive signal being associated with a switching frequency related to the power converter including the switch;
• wherein the comparator and the driving component are configured to, in response to at least the third input signal, change a peak value of the primary current within a first predetermined range and change the switching frequency of the power converter within a second predetermined range.

A method for regulating a power converter, the method comprising:

• receiving a first input signal and a second input signal, the first input signal including a third input signal and being associated with at least a feedback signal related to an output voltage of a power converter, the second input signal being associated with at least a primary current flowing through a primary winding of the power converter;
• processing information associated with the first input signal and the second input signal;
• generating a comparison signal based on at least information associated with the first input signal and the second input signal;
• receiving the comparison signal;
• processing information associated with the comparison signal;
• outputting a drive signal to a switch based on at least information associated with the comparison signal, the drive signal being associated with a switching frequency related to the power converter including the switch;
• changing, in response to at least the third input signal, a peak value of the primary current within a first predetermined range;
• and
• changing, in response to at least the third input signal, the switching frequency of the power converter within a second predetermined range.